Monitoring a sleeping subject

ABSTRACT

Apparatus and methods are described, including apparatus for use with a subject who shares a bed with a second person. A motion sensor detects motion of the subject and motion of the second person, and generates a motion signal in response thereto. A control unit identifies components of the motion signal that were generated in response to motion of the subject, by distinguishing between components of the motion signal that were generated in response to motion of the subject, and components of the motion signal that were generated in response to motion of the second person. The control unit analyzes the components of the motion signal that were generated in response to motion of the subject and generates an output in response thereto. Other applications are also described.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.16/398,572, issued as U.S. Pat. No. 11,147,476, which is a continuationof U.S. application Ser. No. 14/474,357, issued as U.S. Pat. No.10,292,625 which is a continuation-in-part of:

(a) U.S. application Ser. No. 13/906,325 to Halperin, issued as U.S.Pat. No. 8,882,684, filed May 30, 2013, which is a continuation-in-partof:

(i) U.S. patent application Ser. No. 13/389,200, filed Jun. 13, 2012(published as US 2012/0253142, now abandoned), which is a US nationalphase of International Application PCT/IL2011/050045 (published as WO12/077113), filed Dec. 7, 2011, which claims the benefit of thefollowing U.S. provisional patent applications:

U.S. Provisional Application 61/420,402, filed Dec. 7, 2010;

U.S. Provisional Application 61/439,971, filed Feb. 7, 2011; and

U.S. Provisional Application 61/561,962, filed Nov. 21, 2011; and

(ii) International Application PCT/IL2013/050283 (published as WO13/150523), filed Mar. 24, 2013, which claims priority from thefollowing U.S. provisional patent applications:

U.S. Provisional Patent Application No. 61/618,792, filed Apr. 1, 2012;

U.S. Provisional Patent Application No. 61/696,326, filed Sep. 4, 2012;

U.S. Provisional Patent Application No. 61/698,736, filed Sep. 10, 2012;

U.S. Provisional Patent Application No. 61/722,810, filed Nov. 6, 2012;

U.S. Provisional Patent Application No. 61/725,513, filed Nov. 13, 2012;

U.S. Provisional Patent Application No. 61/739,033, filed Dec. 19, 2012;

U.S. Provisional Patent Application No. 61/748,081, filed Jan. 1, 2013;

U.S. Provisional Patent Application No. 61/756,003, filed Jan. 24, 2013;

U.S. Provisional Patent Application No. 61/757,739, filed Jan. 29, 2013;

U.S. Provisional Patent Application No. 61/764,541, filed Feb. 14, 2013;and

U.S. Provisional Patent Application No. 61/772,553, filed Mar. 5, 2013;and

(b) International Application PCT/IL2014/050644 (published as WO15/008285), filed Jul. 17, 2014, which claims the benefit of (i) U.S.Provisional Application 61/847,579, filed Jul. 18, 2013, and (ii) U.S.Provisional Application 61/926,499, filed Jan. 13, 2014.

Each of the above-referenced applications is assigned to the assignee ofthe present application and is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to monitoring subjects andpredicting and monitoring abnormal physiological conditions and treatingthose conditions, and specifically to methods and apparatus forpredicting and monitoring abnormal physiological conditions bynon-contact measurement and analysis of characteristics of physiologicaland/or physical parameters.

BACKGROUND

Chronic diseases are often expressed by episodic worsening of clinicalsymptoms. Preventive treatment of chronic diseases reduces the overalldosage of required medication and associated side effects, and lowersmortality and morbidity. Generally, preventive treatment should beinitiated or intensified as soon as the earliest clinical symptoms aredetected, in order to prevent progression and worsening of the clinicalepisode and to stop and reverse the pathophysiological process.Therefore, the ability to accurately monitor pre-episodic indicatorsincreases the effectiveness of preventive treatment of chronic diseases.

Many chronic diseases cause systemic changes in vital signs, such asbreathing and heartbeat patterns, through a variety of physiologicalmechanisms. For example, common respiratory disorders, such as asthma,chronic obstructive pulmonary disease (COPD), sleep apnea and cysticfibrosis (CF), are direct modifiers of breathing and/or heartbeatpatterns. Other chronic diseases, such as diabetes, epilepsy, andcertain heart conditions (e.g., congestive heart failure (CHF)), arealso known to modify cardiac and breathing activity. In the case ofcertain heart conditions, such modifications typically occur because ofpathophysiologies related to fluid retention and general cardiovascularinsufficiency. Other signs such as coughing and sleep restlessness arealso known to be of importance in some clinical situations.

Many chronic diseases induce systemic effects on vital signs. Forexample, some chronic diseases interfere with normal breathing andcardiac processes during wakefulness and sleep, causing abnormalbreathing and heartbeat patterns.

Breathing and heartbeat patterns may be modified via various direct andindirect physiological mechanisms, resulting in abnormal patternsrelated to the cause of modification. Some respiratory diseases, such asasthma, and some heart conditions, such as CHF, are direct breathingmodifiers. Other metabolic abnormalities, such as hypoglycemia and otherneurological pathologies affecting autonomic nervous system activity,are indirect breathing modifiers.

SUMMARY

Some applications of the present invention provide methods and systemsfor monitoring subjects for the occurrence or recurrence of aphysiological event, for example, a chronic illness or ailment. Thismonitoring assists the subject or healthcare provider in treating theailment or mitigating the effects of the ailment. Some applications ofthe present invention provide techniques for monitoring vital andnon-vital signs using automated sensors and electronic signalprocessing, in order to detect and characterize the onset of aphysiological event, and, for some applications, to treat the event,such as with therapy or medication.

In some cases, a subject is monitored not to predict or track diseasesituations, but rather, in order to allow the subject to optimize longterm health and fitness as part of a ‘wellness’ approach, and/or inorder to control household devices (e.g., bedside lamps, mobile phones,alarm clocks, etc.) in a manner that increases their usefulness and/orminimizes the disturbances causes by these devices.

There is therefore provided, in accordance with some applications of thepresent invention, apparatus for use with a subject who shares a bedwith a second person, the apparatus including:

a motion sensor configured to:

detect motion of the subject without contacting the subject, withoutcontacting clothes the subject is wearing, without viewing the subject,and without viewing clothes the subject is wearing,

detect motion of the second person without contacting the second person,without contacting clothes the second person is wearing, without viewingthe second person, and without viewing clothes the second person iswearing, and

generate a motion signal in response to detecting motion of the subjectand motion of the second person; and

a control unit configured to:

identify components of the motion signal that were generated in responseto motion of the subject, by distinguishing between components of themotion signal that were generated in response to motion of the subject,and components of the motion signal that were generated in response tomotion of the second person,

analyze the components of the motion signal that were generated inresponse to motion of the subject, and

generate an output in response thereto.

In some applications, the control unit is configured to identifycomponents of the motion signal that were generated in response tomotion of the subject, by identifying components of the motion signalthat have a signal strength that is a characteristic signal strength ofa motion signal of the subject.

In some applications, the control unit is configured to identifycomponents of the motion signal that were generated in response tomotion of the subject by identifying components of the motion signalthat have a pattern that is a characteristic pattern of motion of thesubject.

In some applications, the apparatus further includes a weight sensorthat is configured to detect when the subject is lying above the motionsensor, and the control unit is configured to identify the components ofthe motion signal that were generated in response to motion of thesubject, in response to a signal that is generated by the weight sensor.

In some applications, the motion sensor is configured to facilitate theidentification of components of the motion signal that were generated inresponse to motion of the subject, by strengthening a signal strength ofthe components of the motion signal that are generated in response tomotion of the subject.

In some applications, the apparatus is for use with a subject who lieson a mattress, and the sensor is configured to be placed at a positionselected from the group consisting of: underneath the mattress at aposition that is higher than a head of the subject is typically placed,and adjacent to and in contact with a side of the mattress.

In some applications, the sensor is configured such as to facilitateidentification, by the control unit, of components of the motion signalthat were generated in response to a longitudinal cardio-ballisticeffect of the subject.

In some applications, the control unit is configured to identifycomponents of the motion signal that were generated in response torespiratory motion of the subject.

In some applications, the control unit is configured to identifycomponents of the motion signal that were generated in response tocardiac motion of the subject.

In some applications, the control unit is configured to identifycomponents of the motion signal that were generated in response to largebody-movement of the subject.

In some applications, the control unit is further configured to:

analyze the motion signal,

in response thereto, identify an effect of large body-movement of thesecond person on sleep of the subject, and

in response thereto, generate a sleep-disturbance output.

In some applications, the sleep-disturbance output includes anassessment of an effectiveness of a parameter at reducing the effect ofthe large body-movement of the second person on the sleep of thesubject, the control unit being configured to generate the assessment ofthe effectiveness of the parameter.

In some applications, the parameter is selected from the groupconsisting of: a parameter of a mattress on which the subject issleeping, a parameter of the bed, a sleeping arrangement of the subjectand the second person, and a room-environment parameter, the controlunit being configured to generate the assessment of the effectiveness ofthe selected parameter.

In some applications, the sleep-disturbance output includes arecommendation to reduce the effect of the large body-movement of thesecond person on the sleep of the subject by adjusting an adjustableparameter, the control unit being configured to generate therecommendation.

In some applications, the adjustable parameter is selected from thegroup consisting of: a parameter of a mattress on which the subject issleeping, a parameter of the bed, a sleeping arrangement of the subjectand the second person, and a room-environment parameter, the controlunit being configured to generate the recommendation to adjust theselected parameter.

In some applications, the sleep-disturbance output includes instructionsto a device to adjust an adjustable parameter, the control unit beingconfigured to generate the instructions.

In some applications, the adjustable parameter is selected from thegroup consisting of: a parameter of a mattress on which the subject issleeping, a parameter of the bed, a sleeping arrangement of the subjectand the second person, and a room-environment parameter, the controlunit being configured to generate the instructions to the device toadjust the selected parameter.

In some applications,

the motion sensor includes a mechanical-filtering element configured toreduce a response of the motion sensor to motion of the second person,relative to motion of the subject, and

the control unit is further configured to:

by analyzing the motion signal, assess an effectiveness of themechanical-filtering element at reducing the response of the motionsensor to motion of the second person, and

generate an output in response thereto.

In some applications, the control unit is configured to identify that aportion of the motion signal was generated in response to motion of thesecond person, and not in response to motion of the subject, byidentifying that the portion exhibits ringing.

In some applications, the motion sensor consists of a single motionsensor.

The present invention will be more fully understood from the followingdetailed description of embodiments thereof, taken together with thedrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a system for monitoring a chronicmedical condition of a subject, in accordance with some applications ofthe present invention;

FIG. 2 is a schematic block diagram illustrating components of a controlunit of the system of FIG. 1, in accordance with some applications ofthe present invention;

FIG. 3 is a schematic block diagram illustrating a breathing patternanalysis module of the control unit of FIG. 2, in accordance with someapplications of the present invention;

FIG. 4 is a schematic block diagram illustrating additional componentsof a pattern analysis module of the control unit of FIG. 2, inaccordance with some applications of the present invention;

FIG. 5 is a schematic illustration of a semi-rigid sensor plate that isused as a motion sensor, in accordance with some applications of thepresent invention;

FIGS. 6A-B are schematic illustrations of a motion sensor coupled to achair, in accordance with some applications of the present invention;

FIG. 7 is a schematic illustration of apparatus for identifyinginefficient respiration of a subject, in accordance with someapplications of the present invention;

FIG. 8 is a schematic illustration of a method for detecting ectopicheartbeats, in accordance with some applications of the presentinvention;

FIGS. 9A-B are schematic illustrations of a motion sensor comprising asensor plate, in accordance with some applications of the presentinvention;

FIGS. 10A-D are schematic illustrations of a sensor-holding plate, inaccordance with some applications of the present invention;

FIG. 11 is a schematic illustration of apparatus comprising a motionsensor, control unit, and speaker, in accordance with some applicationsof the present invention;

FIG. 12 is a schematic illustration of apparatus comprising a motionsensor, control unit, and alarm clock, in accordance with someapplications of the present invention;

FIG. 13 is a schematic illustration of a motion sensor powered by apower supply and rechargeable battery, in accordance with someapplications of the present invention;

FIG. 14 is a schematic illustration of apparatus for controlling athermoregulation device, in accordance with some applications of thepresent invention;

FIG. 15 is a schematic illustration of a sensor configured to be placedwithin a pillow, in accordance with some applications of the presentinvention;

FIG. 16 is a schematic illustration of ballistocardiographic signalsused for calculating an indication of a left-ventricular-ejection-time,in accordance with some applications of the present invention;

FIG. 17 is a schematic illustration of apparatus for use with aplurality of sleeping subjects, in accordance with some applications ofthe present invention;

FIG. 18 is a schematic illustration of apparatus for activating amedical device for a subject who is sleeping in proximity to at leastone other person, in accordance with some applications of the presentinvention;

FIGS. 19-20 are schematic illustrations of apparatus for use with aperson who is on a resting surface and for use with an illuminator, inaccordance with some applications of the present invention;

FIG. 21 is a schematic illustration of apparatus for use with a wakingmechanism that executes a waking routine to wake a subject who issleeping near a second person, in accordance with some applications ofthe present invention;

FIG. 22 is a schematic illustration of apparatus for use with a wakingmechanism that executes a waking routine to wake a subject who is on aresting surface, in accordance with some applications of the presentinvention;

FIG. 23 is a schematic illustration of apparatus for use with (i) awaking mechanism that executes a waking routine to wake a subject who ison a resting surface, and (ii) an output unit, in accordance with someapplications of the present invention;

FIG. 24 is a schematic illustration of apparatus for identifying aposture of a subject, in accordance with some applications of thepresent invention;

FIG. 25 is a schematic illustration of apparatus for monitoring asubject, in accordance with some applications of the present invention;and

FIG. 26 is a schematic illustration of apparatus for monitoring asubject, in accordance with some applications of the present invention.

FIG. 27A is a schematic illustration of apparatus comprising a motionsensor, a mains-power-connection device, and a control unit, inaccordance with some applications of the present invention;

FIG. 27B is a schematic illustration of a mains-power-connection device,in accordance with some applications of the present invention;

FIGS. 28 and 29 are schematic illustrations of apparatus for use with aburglar alarm, in accordance with some applications of the presentinvention;

FIG. 30 is a schematic illustration of apparatus for use with a burglaralarm, in accordance with some applications of the present invention;

FIG. 31 is a schematic illustration of various apparatus for use with asubject who shares a bed with a second person, in accordance with someapplications of the present invention;

FIG. 32 is a plot of a motion signal that includes a portion thereofthat exhibits ringing, as analyzed in accordance with some applicationsof the present invention; and

FIGS. 33A-B are schematic illustrations of respective views of a motionsensor, in accordance with some applications of the present invention.

DETAILED DESCRIPTION

FIG. 1 is a schematic illustration of a system 10 for monitoring achronic medical condition of a subject 12, in accordance with someapplications of the present invention. System 10 typically comprises amotion sensor 30, a control unit 14, and a user interface (U/I) 24.System 10 is generally similar to system 10 described in US 2011/0112442to Meger and in US 2012/0253142 to Meger, both of which applications areincorporated herein by reference, except for differences describedherein. For some applications, user interface 24 is integrated intocontrol unit 14, as shown in the figure, while for other applications,the user interface and the control unit are separate units. Typically,user interface 24 includes a display. For some applications, motionsensor 30 is integrated into control unit 14, in which case userinterface 24 is either also integrated into control unit 14 or remotefrom control unit 14. For some applications, control unit 14 and/or userinterface 24 of system 10 are implemented in a mobile device (such as acellular phone, a pager, and/or a tablet computer).

In some applications of the present invention, motion sensor 30 is a“non-contact sensor,” that is, a sensor that does not contact the bodyof subject 12 or clothes subject 12 is wearing. In other applications,motion sensor 30 does contact the body of subject 12 or clothes subject12 is wearing. In the former applications, because motion sensor 30 doesnot come in contact with subject 12, motion sensor 30 detects motion ofsubject 12 without discomforting or inconveniencing subject 12. For someapplications, motion sensor 30 performs sensing without the knowledge ofsubject 12, and even, for some applications, without the consent ofsubject 12. For some applications, motion sensor 30 does not have adirect line of sight with subject 12 or the clothes subject 12 iswearing.

(It is noted that generally, in the present description, the term“motion sensor 30” is used to refer to a sensor that does not contact orview the subject or clothes the subject is wearing, while the term“sensor 316” refers more generally to any type of sensor, e.g., a sensorthat includes an electromyographic sensor and/or an imaging sensor.Thus, a phrase such as “sensor 316 (e.g., motion sensor 30)” should beconstrued to mean that the scope of the described invention includes theuse of any type of sensor, but specifically, a non-contact andnon-viewing sensor may be used.)

Motion sensor 30 may comprise a ceramic piezoelectric sensor, vibrationsensor, pressure sensor, or strain sensor, for example, a strain gauge,configured to be installed under a resting surface 37, and to sensemotion of subject 12. The motion of subject 12 sensed by sensor 30,during sleep, for example, may include regular breathing movement,heartbeat-related movement, and other, unrelated body movements, asdiscussed below, or combinations thereof. For some applications, sensor30 comprises a standard communication interface (e.g. USB), whichenables connection to standard monitoring equipment.

As shown in FIG. 2 (described hereinbelow), for some applications, inaddition to wirelessly-enabled motion sensor 30, control unit 14 iscoupled to one or more additional sensors 60 applied to subject 12, suchas a blood oxygen monitor 86 (e.g., a pulseoximeter/photoplethysmograph), an ECG monitor 62, weight sensor 81 (e.g.a weight sensor embedded into a bed as manufactured by Stryker Inc. ofKalamazoo, Mich.), a moisture sensor 85, an angle sensor 87, and/or atemperature sensor 80. In accordance with respective applications, oneor more of sensors 60 is a contact sensor or a contact-less sensor.

Most of the experimental results presented in the present applicationwere measured using one or more piezoelectric sensors. Nevertheless, thescope of the present invention includes performing measurements withother motion sensors 30, such as other pressure gauges oraccelerometers.

Motion sensor 30 is typically coupled to a resting surface 37 upon whichthe subject rests. For example, as shown in FIG. 1, motion sensor 30 maybe placed under a mattress of a bed, and may sense motion of the subjectwhile the subject is in the bed, and generate a motion sensor signal inresponse thereto. Alternatively or additionally, as shown in FIGS. 6A-Band as described in further detail in US 2013/0267791 to Halperin, whichis incorporated herein by reference, motion sensor 30 may be coupled toa chair (e.g., a wheelchair) upon which the subject sits, and may sensemotion of the subject while the subject is sitting in the chair, andgenerate a motion sensor signal in response thereto. For someapplications, system 10 includes a first motion sensor which is underthe mattress of the subject's bed, and a second motion sensor 30, whichis coupled to a chair in the subject's room. The first sensor sensesmotion of the subject while the subject is in the bed, and the secondmotion sensor senses motion of the subject while the subject is in thechair. System 10 monitors the subject responsively to both the first andthe second sensor signals, as described in US 2013/0267791 to Halperin,which is incorporated herein by reference. For some applications, aplurality of motion sensors are coupled to a single resting surface, andare used as motion sensor 30. For example, two or more motion sensorsthat are disposed under the subject's mattress may be used as motionsensor 30. Alternatively, only a single sensor is coupled to a givenresting surface.

FIG. 2 is a schematic block diagram illustrating components of controlunit 14 in accordance with some applications of the present invention.Control unit 14 typically comprises a motion data acquisition module 20and a pattern analysis module 16. Pattern analysis module 16 typicallycomprises one or more of the following modules: a breathing patternanalysis module 22, a heartbeat pattern analysis module 23, a coughanalysis module 26, a restlessness analysis module 28, a blood pressureanalysis module 29, and an arousal analysis module 31. For someapplications, pattern analysis module includes additional modules and/orfunctionalities to those shown in FIG. 2. For example, pattern analysismodule 16 may include one or more of the additional modules and/orfunctionalities shown in FIG. 4. For some applications, two or more ofanalysis modules 20, 22, 23, 26, 28, 29, and 31 (and/or the additionalmodules and/or functionalities) are packaged in a single housing. Forother applications, the modules are packaged separately (for example, soas to enable remote analysis, by one or more of the pattern analysismodules, of breathing signals acquired locally by data acquisitionmodule 20).

User interface 24 typically comprises a dedicated display unit, such asan LCD or CRT monitor. Alternatively or additionally, the user interface24 comprises a wireless or wired communication port for relaying theacquired raw data and/or processed data to a remote site for furtheranalysis, interpretation, expert review, and/or clinical follow-up. Forexample, the data may be transferred over a telephone line, and/or overthe Internet or another wide-area network, either wirelessly or viawires.

Breathing pattern analysis module 22 is configured to extract breathingpatterns from the motion data, as described hereinbelow with referenceto FIG. 3, and heartbeat pattern analysis module 23 is configured toextract heartbeat patterns from the motion data. Alternatively oradditionally, system 10 comprises another type of sensor, such as anacoustic or air-flow sensor attached or directed at the subject's face,neck, chest, and/or back, or placed under the mattress.

FIG. 3 is a schematic block diagram illustrating components of breathingpattern analysis module 22, in accordance with some applications of thepresent invention. Breathing pattern analysis module 22 analyzes changesin breathing patterns, typically during sleep. Breathing patternanalysis module 22 typically comprises a digital signal processor (DSP)41, a dual port RAM (DPR) 42, an EEPROM 44, and an I/O port 46. Modules23, 26, 28, 29, and 31 may be similar to module 22 shown in FIG. 3. Forexample, modules 23, 26, 28, 29, and 31 may include a digital signalprocessor, a dual port RAM, an EEPROM, and an I/O port similar todigital signal processor 41, dual port RAM 42, EEPROM 44, and I/O port46. Breathing pattern analysis module 22 may be used (e.g., tofacilitate ascertaining a sleep stage of a subject) with variousapparatus and methods described herein, such as, for example, apparatus334, described hereinbelow with reference to FIGS. 19-20.

In some applications of the present invention, data acquisition module20 is configured to non-invasively monitor breathing and heartbeatpatterns of subject 12. Breathing pattern analysis module 22 andheartbeat pattern analysis module 23 are configured to extract breathingpatterns and heartbeat patterns respectively from the raw data generatedby data acquisition module 20, and to perform processing andclassification of the breathing patterns and the heartbeat patterns,respectively. Breathing pattern analysis module 22 and heartbeat patternanalysis module 23 are configured to analyze the respective patterns inorder to (a) predict an approaching clinical episode, such as an asthmaattack, heart condition-related lung fluid buildup, sepsis, cardiacarrest, or respiratory depression, and/or (b) monitor the severity andprogression of a clinical episode as it occurs. User interface 24 isconfigured to notify subject 12 and/or a clinician of the predicted oroccurring episode. Prediction of an approaching clinical episodefacilitates early preventive treatment, which generally improvesoutcomes, e.g., by lowering required dosages of medication, and/orlowering mortality and morbidity. When treating a hospitalized subjectin a general care ward, for example, an earlier identification ofsubject deterioration may prevent the need to admit the subject to theICU, shorten his length of stay, and increase the likelihood forsuccessful recovery to discharge.

Breathing pattern analysis module 22 and heartbeat pattern analysismodule typically derive breathing patterns and heartbeat patterns fromthe raw data in accordance with the techniques described in US2011/0112442 to Meger and in US 2012/0253142 to Meger, both of whichapplications are incorporated herein by reference. In general, system 10is configured to monitor clinical parameters of the subject, and togenerate alerts and/or reports in response thereto, in a generallysimilar manner to system 10 described US 2011/0112442 to Meger and in US2012/0253142 to Meger, both of which applications are incorporatedherein by reference.

Reference is now made to FIG. 4, which is a schematic illustration offunctionalities and/or modules that are included in pattern analysismodule 16, in addition to the modules of the pattern analysis modulethat are shown in FIG. 2, in accordance with some applications of thepresent invention. Typically, pattern analysis module includes signalanalysis functionality 90. The signal analysis functionality isconfigured to analyze the signals received from the sensors that provideinput to control unit 14 and to determine a condition of the subjectand/or generate an output (e.g., an alert), in response thereto. Many ofthe functionalities of control unit 14 that are described herein asbeing performed by pattern analysis module 16 are performed by thesignal analysis functionality of the pattern analysis module. Patternanalysis module typically further includesalert-generation-functionality 92 that is configured to generate analert in response to the signal analysis that is performed by the signalanalysis functionality. For example, alerts may be generated on pagersof clinicians, at user interface (e.g., display) 24, and/or at a centralmonitoring system user interface (e.g., display). For some applications,pattern analysis module includes score calculating functionality 100configured to calculate a score in response to the signal analysis thatis performed by the signal analysis functionality. In accordance withsome applications, pattern analysis module includes additionalfunctionalities and/or modules, such as ashallow-breathing-pattern-identification functionality 101, a subjectidentification module 102, a subject-position-identificationfunctionality 104, an irregular-sleep-detection functionality 106, adecreasing-cardioballistic-amplitude-detection functionality 108, acardiac-arrhythmia-detection functionality 110, an inefficientrespiration identification functionality 111, a cardiac-risk-detectionfunctionality 112, protocol input functionality 114,athletic-exercise-receiving functionality 116, and/ornutrition-receiving functionality 118. The functions of at least some ofthe additional functionalities and/or modules are described in furtherdetail hereinbelow.

For some applications, the pattern analysis module includes subjectidentification module 102. The subject identification module isconfigured to determine which motion signals detected by motion sensor30 were generated by the subject. For example, in cases in which thesubject who is being monitored is sharing a bed with a second person(e.g., the subject's partner), the subject identification moduledetermines which components of the motion signal detected by the motionsensor were generated by the subject and which were generated by thesecond person. The pattern analysis module then analyzes the componentsof the signal that were generated by the subject, and generates outputs(such as alerts), as described herein, in response thereto. For someapplications, the subject identification module is configured todetermine when the subject is out of bed by determining that the motionsignal detected by the motion detector is being generated by the secondperson. For some applications, the subject identification module isconfigured to determine which components of the motion signal detectedby the motion sensor were generated by the subject even when the subjectis smaller than the second person.

For some applications, subject identification module 102 is configuredto determine which components of the motion signal detected by motionsensor 30 were generated by the subject using one or more of thefollowing techniques:

a. The subject identification module identifies patterns (e.g., arespiratory pattern, a heart rate pattern, and/or a motion pattern,e.g., a large body-movement pattern) that are characteristic of,respectively, the subject and the second person. The subjectidentification module then determines that components of the signal thatcorrespond to the characteristic patterns of the subject have beengenerated by the subject. For some applications, the subjectidentification module learns characteristic patterns of the subject byutilizing a weight sensor (e.g., as described hereinbelow), and/or orutilizing long term average patterns of the subject. For someapplications, in response to an input to system 10, the patternidentification module operates in a learning mode, in which the modulelearns characteristic patterns of the subject.

b. The subject identification module identifies characteristic signalstrengths generated, respectively, by the subject and by the secondperson. For example, the sensor may be disposed underneath the subjectwho lies on a first side of the bed and the second person may typicallylie on the second side of the bed. In such cases, signals generated bythe subject are typically characterized as being of greater strengththan those generated by the second person. Alternatively, the subjectmay be smaller than the second person, and may therefore generatesignals that are characterized as being weaker than signals generated bythe second person.

Reference is now made to FIGS. 33A-B, which are schematic illustrationsof respective views of motion sensor 30, in accordance with someapplications of the present invention. For some applications, motionsensor 30 is configured to facilitate determination by subjectidentification module 102 of which components of the motion signal weregenerated by the subject. For example, the sensor may be placed in aposition, and/or shaped, such as to strengthen the signal that isreceived from the subject. For some applications, the sensor is placedunderneath the subject's mattress at a position higher than where thesubject rests his/her head, such that the strongest signals that thesensor receives are those generated by the longitudinal cardio-ballisticeffect of the subject. Alternatively or additionally, at least a portionof the sensor is placed adjacent to and in contact with a side of thesubject's mattress (e.g., the head of the subject's mattress), and notunderneath the mattress. For some applications, the motion sensorcomprises at least a portion of an L-shaped structure, as shown in FIGS.33A-B. The structure is shaped to define horizontal and verticalportions that form approximately (or precisely) a right angle with oneanother. The horizontal portion of the structure is placed underneaththe subject's mattress, and the vertical portion of the structure isplaced adjacent to and in contact with a side of the subject's mattress(e.g., the head of the subject's mattress). For some applications, thehorizontal portion of the structure does not perform any sensingfunctionalities but acts as a support element 49 for supporting thevertical portion adjacent to and in contact with a side of the subject'smattress (e.g., the head of the subject's mattress), the verticalportion acting as sensor 30.

Alternatively or additionally, a different support element is used tosupport sensor 30 at a position adjacent to and in contact with a sideof the subject's mattress (e.g., the head of the subject's mattress).For example, a compressible member (such as a cushion) may be placedbetween the side of the mattress and a surface (e.g., a wall or aheadboard) that is adjacent to the side of the mattress, and may beconfigured to hold the sensor against the head of the mattress, byexpanding against the side of the mattress. For some applications, thesensor is disposed on a stretchable band (e.g., an elastic band). Theband is stretched in order to facilitate placement of the band aroundthe sides of the subject's mattress, and the band then shrinks, such asto maintain the sensor adjacent to and in contact with a side of thesubject's mattress (e.g., the head of the subject's mattress). For someapplications, the sensor is not disposed on a stretchable band, but thesensor is maintained adjacent to and in contact with a side of thesubject's mattress (e.g., the head of the subject's mattress), using astretchable band.

For some applications, the motion sensor includes a weight sensor thatis configured to measure a weight that is placed on top of the weightsensor, and to identify that the subject is lying above the motionsensor in response thereto. The subject identification module identifiessignals from the motion sensor as having been generated by the subject,in response to the signal generated by the weight sensor. For someapplications, the weight sensor is used to determine when the subject isdirectly on top of the weight sensor. In response to determining thatthe subject is directly on top of the weight sensor, the patternidentification module operates in a learning mode, in which the modulelearns characteristic patterns of the subject, as described hereinabove.For some applications, respective first and second motion sensors areplaced underneath the subject and the second person who uses the bed.Subject identification module 102 determines which components of themotion signal were generated by the subject in response to the signalsfrom both the first and the second motion sensors.

The above-described apparatus and techniques for subject identificationmay be utilized in combination with other apparatus and techniquesdescribed herein, such as, for example, apparatus and techniquesdescribed with reference to FIG. 32.

Reference is now made to FIG. 7, which is a schematic illustration ofapparatus for identifying inefficient respiration of a subject 234, inaccordance with some applications of the present invention. Inefficientrespiration may be indicative of a clinical episode related to arespiratory disorder such as obstructive apnea or asthma. Inefficientrespiration corresponds to a situation in which the respirationmovements are large relative to the volume of respiration flow. Thisphenomenon may occur in one of the two following ways:

1) Respiration movements are normal, but the volume of respiration flowis abnormally low.

2) The volume of respiration flow is normal, but respiration movementsare abnormally large, such as where the subject needs to use upper-bodymuscles that are normally not used for respiration.

Reference is now made to FIGS. 4 and 7. In some applications, patternanalysis module 16 of control unit 14 comprises inefficient respirationidentification functionality 111, as described hereinabove with respectto FIG. 4. The identification of inefficient respiration typicallyproceeds according to the following steps:

1. A respiration-related motion signal is identified in the mechanicalsensor signal that is detected by sensor 30. The amplitude of thissignal corresponds to the respiration movements of the subject.

2. The volume of respiration flow is measured, e.g., using a respirationflow meter 236 or sensor 30. (Respiration flow meter 236 may be handledby the subject, or alternatively, by a caregiver, e.g., a physician ornurse.)

3. The inefficient respiration identification functionality calculates arelationship of the amplitude of the respiration-related motion signalto the volume of respiration flow, and inefficient respiration isidentified in response to this relationship. For example, therelationship may comprise the quotient of the quantities, e.g.,Amplitude of Signal/Volume of Flow. The quotient is compared to abaseline value, and inefficient respiration is identified in response tothis comparison. For example, inefficient respiration may be identifiedif the quotient of Amplitude/Volume is increased by a factor of at least1.5 relative to the baseline value (e.g., the factor may be 2).

Identifying the inefficient respiration in response to a relationshipbetween the quantities, rather than based on the absolute values of thequantities, helps facilitate the identification of inefficientrespiration even if one of the quantities is normal, as describedhereinabove.

Reference is now made to FIG. 8, which is a schematic illustration of amethod for detecting ectopic heartbeats, e.g., premature ventricularcontractions, in accordance with some applications of the presentinvention. For some applications, heartbeat pattern analysis module 23(FIG. 2) is configured to detect ectopic beats of a subject. The cardiacsignal component of the sensor signal generated by sensor 30 is filteredinto a high-frequency component 206 and a low-frequency component 204.(Components 204 and 206 are shown plotted in arbitrary units in FIG. 8.)Since both normal and ectopic beats exhibit high-frequencycharacteristics indicative of ventricular contraction, the highfrequency component indicates both normal and ectopic beats. On theother hand, ectopic beats lack some low-frequency characteristicsindicative of blood flow; consequently, the low frequency componentgenerally indicates normal (but not ectopic) beats. Portions 200 of thehigh-frequency component, corresponding to ventricular contractions ofthe subject, are identified by heartbeat pattern analysis module 23; apair of such portions typically indicates a single heartbeat. For eachpair of portions 200, a corresponding portion of the low-frequencycomponent is analyzed. If this corresponding portion is indicative ofblood flow, e.g., as shown in portions 202 (solid line), the heartbeatis determined to be a normal beat. Conversely, if the correspondingportion is not indicative of blood flow, e.g., as shown in portions 208(dashed line), the heartbeat is determined to be an ectopic beat. Forexample, as shown in FIG. 8, a pair 201 of portions 200 corresponds to aportion 202 indicative of blood flow, while a pair 210 of portions 200corresponds to a portion 208 which is not indicative of blood flow.

In some applications, the time between the two elements of a pair ofportions 200 is used to diagnose cardiac conditions such as earlyheartbeats, missing heartbeats, and low stroke volume.

Filtering of the signal into high-frequency and low-frequency componentsis typically done using band-pass filters. In some applications, thelower cutoff frequency for the low-frequency band-pass filter may be,for example, at least 1.5 and/or less than 4 Hz (e.g., 2 Hz), while thehigher cutoff frequency may be, for example, at least 4.1 and/or lessthan 7.5 Hz (e.g., 5 Hz). The lower cutoff frequency for thehigh-frequency band-pass filter may be, for example, at least 6.5 and/orless than 11.5 Hz (e.g., 9 Hz), while the higher cutoff frequency maybe, for example, at least 11.6 and/or less than 16.5 Hz (e.g., 14 Hz).In other applications, the lower cutoff frequency for the low-frequencyband-pass filter may be, for example, at least 2.5 and/or less than 3.5Hz, while the higher cutoff frequency may be, for example, at least 4.5and/or less than 5.5 Hz. The lower cutoff frequency for thehigh-frequency band-pass filter may be, for example, at least 8.5 and/orless than 9.5 Hz, while the higher cutoff frequency may be, for example,at least 13.5 and/or less than 14.5 Hz.

Reference is now made to FIG. 5, which is a schematic illustration of asemi-rigid sensor plate 140 that is used as motion sensor 30, inaccordance with some applications of the present invention. For someapplications, the sensor is designed and/or placed under the subject'sbed such as to detect only motion of the subject who is lying on theside closer to the sensor. The sensor mechanical properties are designedto collect the vibration mechanical signal only locally from the subjectlying directly on top or very close to the sensor. This allowsmechanical filtering of signals coming from the partner, and detectionof only the signal of the subject on top of the sensor. For someapplications, edges 142 of the sensor plate are hardened with respect toa central portion 144 of the sensor plate. Typically, this preventstorque from the side of the sensor plate from bending the sensor plate,and allows only direct forces generated from on top of the sensor toaffect the plate such as to generate a sensor signal. In someapplications, the sensor hardening on the circumference is achieved bymechanically preventing a 2-5 mm rim of the semi-rigid sensing platefrom vibrating. This typically substantially reduces the signalgenerated by the second person as compared to that generated by thesubject.

Reference is now made to FIGS. 9A-B, which are schematic illustrationsof motion sensor 30 comprising a sensor plate 238, in accordance withsome applications of the present invention. Sensor plate 238 istypically for use with a subject who shares a bed with a second person,e.g., as shown in FIG. 21. As shown in FIG. 9A, sensor plate 238comprises an edge region 227 that is more rigid than a central portion221 of the sensor plate, such as to reduce movement of the plate inresponse to motion of the second person, relative to if edge region 227of the sensor plate were not more rigid than central portion 221. Asdescribed hereinbelow, edge region 227 may take the form of a rigidnoise filter rim 228, and/or a rigid sensor-holding-plate rim 220.

Motion sensor 30 is configured to be placed on the bed such that whenthe subject and the second person are on the bed (e.g., as in FIG. 21),sensor plate 238 is disposed underneath the subject and not disposedunderneath the second person. When a sensor element 366 (e.g., apiezoelectric sensor element) is being held by a sensor-holding plate218 of sensor plate 238, motion sensor 30 detects motion of the subject,by sensor-holding plate 218 moving in response to motion of the subject.(The motion signal generated by motion sensor 30 is then analyzed bycontrol unit 14, as described throughout the present application.) Therelative rigidity of edge region 227 generally reduces the extent towhich motion of the second person is detected by motion sensor 30,relative to motion of the subject. (In the present description, the word“sensor” may sometimes be used to refer to sensor element 366.)

In some applications, a thickness of the edge region (e.g., thickness tdescribed hereinbelow), measured between an inner perimeter of the edgeregion and an outer perimeter of the edge region, is at least 2 mmand/or less than 20 mm, e.g., less than 8 mm.

In some applications, as shown in FIG. 9B, sensor plate 238 comprisessensor-holding plate 218 and a noise filter plate 226 that is distinctfrom sensor-holding plate 218. In such applications, noise filter plate226 is typically shaped to define a noise filter rim 228. Noise filterrim 228 is more rigid than central portion 221 of the sensor-holdingplate, such as to reduce movement of the sensor-holding plate inresponse to motion of the second person, relative to if the noise filterrim were not more rigid than the central portion of the sensor-holdingplate. Thus, noise filter rim 228 allows for mechanical filtering ofsignals coming from the partner, in a manner generally describedhereinabove with respect to edges 142 of sensor plate 140 (FIG. 5).Alternatively or additionally, sensor-holding plate 218 may be shaped todefine a rigid sensor-holding-plate rim 220 (which is more rigid thancentral portion 221), the function of which is generally similar to thatof noise filter rim 228. Typically, a thickness t2 of thesensor-holding-plate rim, measured between an inner perimeter of thesensor-holding-plate rim and an outer perimeter of thesensor-holding-plate rim, is at least 2 mm and/or less than 8 mm, oralternatively, at least 8 mm and/or less than 20 mm.

In some applications, the top of noise filter rim 228 is generally levelwith the top of sensor-holding plate 218, while in other applications,the top of noise filter rim 228 is higher, e.g., it is greater than 1and/or less than 5 mm higher. In some applications, a thickness t ofnoise filter rim 228, measured between an inner perimeter of the noisefilter rim and an outer perimeter of the noise filter rim, is at least 2mm and/or less than 8 mm, e.g., 5 mm.

Typically, sensor-holding plate 218 is shaped to hold sensor element366, e.g., via a sensor receptacle 222, thus allowing for the sensorelement to be coupled to the sensor plate. In some applications, thesensor-holding plate further comprises an electronics receptacle 224,configured to hold electronic circuitry which may include, for example,an amplifier, analog to digital converter, and/or a communicationelement. In other applications, the sensor-holding plate does notcomprise electronics receptacle 224, and the circuitry is disposedoutside of the sensor-holding plate.

In some applications, sensor-holding plate 218 is reversibly couplableto noise filter plate 226. The coupling may be effected, for example, bymeans of sensor-holding-plate rim 220, which is disposed along theperimeter of sensor-holding plate 218 and is configured to fit into agroove 230 disposed along the inside perimeter of noise filter plate226. In some applications, a width of groove 230, measured in adirection from an outer perimeter of the groove toward an innerperimeter of the groove, is greater than 0.05 and/or less than 2 mmgreater than thickness t2 of rim 220.

Reference is now made to FIGS. 10A-D, which are schematic illustrationsof sensor-holding plate 218, in accordance with some applications of thepresent invention. FIG. 10A shows sensor-holding plate 218 with acontinuous rim 220 which appears generally as shown in FIG. 9B. Theinventors hypothesize that for some applications, continuous rim 220facilitates generally isotropic focusing of motion sensor 30, in thatcontinuous rim 220 is generally equally effective at blocking motionfrom all lateral directions.

FIG. 10B shows sensor-holding plate 218 with a discontinuous rim 225,shaped to define a plurality of slots (i.e., openings, or gaps) 223therein, disposed around rim 225. Slots 223 create a “defocusing”effect, i.e., they facilitate the sensing of motion from areas which arenot directly above sensor-holding plate 218. By varying the location,number, and size of slots 223, sensor-holding plate 218 can beconfigured for different beds sizes.

FIG. 10C shows sensor-holding plate 218 with a discontinuous rim 211,shaped to define one or more anisotropically-arranged slots 219 therein.Proper orientation of slots 219 may facilitate the sensing of motionoriginating from one or more particular areas not directly abovesensor-holding plate 218. For example, the sensor-holding plate of FIG.10C may be placed at the head of the bed, oriented such that slot 219 isdirected toward the legs of the subject. In this manner, rim 211 willgenerally prevent the partner's motion from being sensed, whilegenerally allowing the subject's motion to be sensed.

Although FIGS. 10B-C show the sensor-holding-plate rim shaped to defineslots therein, the scope of the present invention includes rims whichcomprise thinned portions which function in a manner generally similarto slots 223 and 219.

In some applications, as shown in FIG. 10D, the rim 229 ofsensor-holding plate 218 may comprise one or more detachable parts 209.The detachment of parts 209 results in the opening of slots such asslots 223 and slots 219. Detachable parts 209 allow for reducing themanufacturing cost of sensor-holding plate 218, since the desired slotscan generally be opened post-manufacture. For example, if the subject issleeping alone and the bed is relatively large, the subject may decideto detach a plurality of small detachable parts 209 to create slots 223,as shown in FIG. 10B, such that motion of the subject is detected evenwhen the subject is not directly over sensor-holding plate 218. In someapplications, parts 209 which have been detached may subsequently bere-attached.

When anisotropically-arranged slots, e.g., slots 219, are used,sensor-holding plate 218 may need to be fixed in place, such that itsorientation remains generally constant. For example, in the case inwhich sensor-holding plate FIG. 10C is to be placed under the head ofthe bed with a slot 219 directed towards the subject's legs,sensor-holding plate 218 may be fixed in place within the subject'spillow, which in general tends to be perpendicular to the subject'slongitudinal axis.

In general, the various applications shown in FIGS. 10A-D may bepracticed in combination with the applications shown in FIGS. 9A-B. Forexample, the various rims that are shown in FIGS. 10A-D may be morerigid than central portion 221, as described hereinabove.

In some applications, as shown in FIGS. 9A-B, sensor-holding plate 218is circular; a sensor-holding plate shaped in this manner has been foundby the inventors to be generally effective in transmitting mechanicalforces to the sensor coupled to the center thereof. In someapplications, the sensor element coupled to sensor-holding plate 218,e.g., via sensor receptacle 222, is also circular. It has been found bythe inventors that the ratio of sensor element diameter (which isgenerally similar to diameter D0 of sensor receptacle 222 shown in FIG.9B) to sensor-holding plate diameter D1 is a relevant factor foreffective transmission of mechanical forces to the sensor. In someapplications of the present invention, the ratio of sensor elementdiameter to sensor-holding plate diameter D1 is greater than 0.1 and/orless than 0.6. In other applications, sensor-holding plate 218 is notcircular, e.g., it may be square or another shape. In theseapplications, noise filter plate 226 is shaped accordingly, such thatthe noise filter is configured to be reversibly couplable to thesensor-holding plate as generally described with respect to FIGS. 9A-B,mutatis mutandis.

In some applications, sensor plate 238 is used in combination withsubject identification module 102, described hereinabove with respect toFIG. 4. Although sensor plate 238 reduces the degree to which motionsensor 30 detects motion of the second person, it is possible that thesensor will nonetheless detect some of this motion. Subjectidentification module 102 therefore identifies components of the motionsignal from sensor 30 that were generated by the subject, bydistinguishing between components of the motion signal that weregenerated respectively by the subject and by the second person, e.g., asdescribed hereinabove. In other applications, subject identificationmodule 102 is used without sensor plate 238.

Reference is now made to FIG. 31, which is a schematic illustration ofvarious apparatus 500 a-e for use with a subject 12 who shares a bedwith a second person 502, in accordance with some applications of thepresent invention. In all of apparatus 500 a-e, motion sensor 30 detectsmotion of subject 12 and motion of second person 502, and generates amotion signal 504 in response thereto. (Motion sensor 30 is typically asingle motion sensor that does not contact or view the subject, clothesthe subject is wearing, the second person, or clothes the second personis wearing.) Furthermore, another common element in apparatus 500 a-e isthat control unit 14 (e.g., via subject identification module 102 (FIG.4)) distinguishes between motion of the subject and motion of the secondperson, i.e., it may identify a particular portion of motion signal 504as coming from the subject or from the second person. On the other hand,apparatus 500 a-e differ from each other in the technique(s) used toperform the distinguishing/subject-identification, in the analysis thatis performed pursuant to the distinguishing/subject-identification,and/or in the output that is generated.

In apparatus 500 a, control unit 14 is configured to identify that aportion of the motion signal was generated in response to motion of thesecond person, and not in response to motion of the subject, byidentifying that the portion exhibits ringing. Reference is made to FIG.32, which is a plot of motion signal 504 that includes a portion 506thereof that exhibits ringing, as analyzed in accordance with someapplications of the present invention. Motion signal 504 includesportions 501 a and 501 b that, respectively, precede and follow portion506. Portions 501 a and 501 b exhibit a generally regular, cyclicalpattern that is typically indicative of the cardiac and respiratorymotion of the subject. Portion 506, on the other hand, has more of astep-response profile, which is typically indicative of largebody-movement. The ringing in portion 506 indicates that the source ofthe large body-movement is the second person, who is not directly abovethe sensor.

To identify the ringing, control unit 14 ascertains that portion 506includes a set of at least three consecutive extrema 508 (i.e., threeconsecutive maxima, or three consecutive minima), each of which(following the first extremum of the set) is separated from thepreceding extremum of the set by a time T₀ that falls within a giventime range (e.g., 0.15-0.45 seconds). (In FIG. 32, two such sets ofconsecutive extrema are shown.) Typically, to identify the ringing,control unit 14 further ascertains that respective differences between(i) magnitudes of consecutive extrema 508, and (ii) a magnitude of anextremum 510 that precedes the set of consecutive extrema (typically aninitial “spike” that precedes the set), fall within a given amplituderange. For example, the control unit may identify that the respectivedifferences are between 10%-150% of the magnitude of extremum 510.Typically, the control unit further ascertains that a difference between(i) a smallest magnitude 512 of the consecutive extrema, and (ii) alargest magnitude 514 of the consecutive extrema, is less than athreshold (e.g., 30% of smallest magnitude 512).

Although FIG. 32 shows the ringing phenomenon only for largebody-movement, ringing may also be exhibited in portions of signal 504that reflect other types of motion, such as respiratory motion orcardiac motion. Apparatus 500 a is configured to identify the secondperson as the source of these other types of motion, by performing theringing-identification techniques described hereinabove.

Apparatus 500 b uses a different technique to identify that a givenportion of the motion signal was generated in response to largebody-movement of the second person, and not in response to motion of thesubject. In apparatus 500 b, control unit 14 is configured to “learn” anamplitude threshold Th by analyzing a portion of the motion signal(e.g., portion 501 a) that was generated in response to motion (e.g.,cardiac and/or respiratory motion) of the subject, and calculatingthreshold Th based on the analysis. (For example, Th may be a multipleof amplitude A4 of portion 501 a.) If the amplitude of a given portionof the motion signal is less than the amplitude threshold, the controlunit identifies that the given portion of the motion signal wasgenerated in response to large body-movement of the second person, andnot in response to motion of the subject. For example, in FIG. 32,extremum 510 is less than Th, such that portion 506 is determined tohave been generated by large body-movement of the second person.

Apparatus 500 c uses yet another technique for distinguishing betweenmotion of the subject and motion of the second person. In apparatus 500c, control unit 14 identifies a subject-motion component of the motionsignal that was generated in response to motion of the subject, e.g.,portions 501 a and 501 b of FIG. 32. To identify whether a givenportion, e.g., portion 506, of the motion signal was generated inresponse to large body-movement of the subject, and not in response tomotion of the second person, control unit 14 compares the amplitude A3of the subject-motion component following the given portion, relative tothe amplitude A4 before the given portion. If the amplitude has changedby a threshold amount, it is likely the subject moved relative to thesensor, and thus, the large body-movement is likely that of the subject.(FIG. 32 shows A4 being different from A3, but not by more than thethreshold amount, such that portion 506 is determined to have beengenerated by motion of the second person.)

In general, the distinguishing/subject-identification techniques ofapparatus 500 a-c are typically combined, i.e., the control unit istypically configured to use any of the techniques described hereinabove,separately or in combination.

Apparatus 500 d also comprises motion sensor 30 and control unit 14, andalso distinguishes between motion of the subject and motion of thesecond person, e.g., using some or all of the techniques of apparatus500 a-c. In apparatus 500 d, control unit 14 is configured to, byanalyzing the signal from motion sensor 30 in an analysis step 518,identify an effect of large body-movement of the second person on sleepof the subject, and in response thereto, generate a sleep-disturbanceoutput 516. Output 516 may include a report (e.g., a digital, and/orprinted, and/or audio report), which may include alphanumeric and/orgraphical content. Alternatively or additionally, as further describedhereinbelow, output 516 may include a recommendation to change aparameter, and/or instructions to a device to change a parameter. Ingeneral, output 516 facilitates the reduction of the extent to whichmovement by second person 502 disturbs the sleep of subject 12.

In some applications, output 516 includes an assessment of aneffectiveness of a parameter at reducing the effect of the largebody-movement of the second person on the sleep of the subject. Forexample, the control unit may assess one or more parameters 520 such as:

(a) a parameter (e.g., a firmness, or a width) of a mattress 522 onwhich the subject is sleeping,

(b) a parameter (e.g., a tilt angle) of bed 37,

(c) a sleeping arrangement of (e.g., a distance between) the subject andthe second person, and/or

(d) a room-environment parameter (e.g., a level of light or sound, or atemperature, in the room).

Some of parameter types (a)-(d) (e.g., a level of light in the room) maybe detected by control unit 14, while other parameter types (e.g., afirmness of mattress 522) are typically received as manual inputs to thecontrol unit.

Typically, in analysis step 518, the control unit analyzes motion signal504 in light of the parameter(s), and generates the assessment inresponse to the analysis. For example, the control unit may compare datafrom several nights of sleep, and/or compare the data from the givenpair of sleepers with data from other pairs of sleepers, to ascertainhow the parameter(s) affect the level of sleep disturbance. Output 516may include, for example, an assessment message such as “A temperaturebetween 23-25° C. in the room is more effective at reducing sleepdisturbance, relative to other temperatures.” Alternatively oradditionally, output 516 may include a recommendation to reduce theeffect of the large body-movement of the second person on the sleep ofthe subject, by adjusting an adjustable parameter such as any ofparameters (a)-(d) listed above. For example, output 516 may include arecommendation message such as “To reduce sleep disturbance, you maywish to reduce the tilt angle of your bed.”

In some applications, apparatus 500 d is used (e.g., by a mattressprovider or consumer) to compare between different types of mattresses.For example, output 516 may include a comparison between (a) theeffectiveness of a parameter of one given type of mattress, and (b) theeffectiveness of the parameter of a different type of mattress. Forexample, output 516 may show a consumer that a firmer mattress is moreeffective than a less-firm mattress at reducing sleep disturbance, andbased on this comparison, the consumer may decide to purchase the firmermattress.

In some applications, output 516 includes instructions to a device 524to adjust an adjustable parameter, e.g., any of (a)-(d) listed above.For example, FIG. 31 shows output 516 including instructions to acontroller 526 to adjust a tilt angle of bed 37.

Apparatus 500 e also comprises motion sensor 30 and control unit 14, andalso distinguishes between motion of the subject and motion of thesecond person, e.g., using some or all of the techniques of apparatus500 a-c. In apparatus 500 e, motion sensor 30 comprises amechanical-filtering element, such as noise filter rim 228 (describedhereinabove with reference to FIGS. 9A-B), which is configured to reducea response of the motion sensor to motion of the second person, relativeto motion of the subject. Control unit 14 analyzes motion signal 504,assesses an effectiveness of the mechanical-filtering element atreducing the response of the motion sensor to motion of the secondperson, and generates an output in response thereto. For example, ifcontrol unit 14 identifies a relatively large number of portions of thesignal coming from motion of the second person, control unit 14 may makean assessment that the mechanical-filtering element is relativelyineffective. In such a case, output 516 may include, for example, arecommendation to replace the current noise filter rim with a thickernoise filter rim.

It is noted that there is a “philosophical” difference between apparatus500 d and apparatus 500 e, in that a typical objective in usingapparatus 500 e is to improve the filtering out of motion from thesecond person (perhaps to the point of near-complete filtering), whereasapparatus 500 d requires that sensor 30 detect at least some of themotion from the second person. Nevertheless, apparatus 500 d and 500 emay be combined, such that a single control unit 14 is configured toperform both the functions of apparatus 500 d and the functions ofapparatus 500 e.

Reference is now made to FIG. 15, which is a schematic illustration of asensor 30 configured to be placed within a pillow 301, in accordancewith some applications of the present invention. In some applications,motion sensor 30 is configured to be placed within pillow 301 of subject12.

Reference is now made to FIG. 11, which is a schematic illustration ofapparatus comprising a motion sensor 30, control unit 14, and speaker232, in accordance with some applications of the present invention. Insome applications of the present invention, motion sensor 30 and aspeaker 232 are configured to be placed under the head of a subject whoshares a bed with another person. (Thus, FIG. 11 depicts resting surface37 as a double bed.) For example, sensor 30 may be placed within thepillow of the subject. Speaker 232 is configured to play musicresponsively to output from control unit 14, for example, in order tohelp the subject fall asleep or use biofeedback techniques to relax. Insome applications, sensor plate 238, described hereinabove with respectto FIGS. 9A-B, is used. The use of sensor plate 238, which, as explainedabove, comprises a more rigid edge region 227 (FIG. 9B), provides thatspeaker 232 responds largely to the sleep stage and physiologicalcondition of the subject, rather than also to motion from the otherperson. In some applications, control unit 14 may eliminate artifactsgenerated by speaker 232 by subtracting the signal generated by thespeaker from the motion signal. The signal generated by speaker 232 maybe received, for example, from the speaker controlling circuit or fromanother sensor on the speaker.

Reference is now made to FIG. 14, which is a schematic illustration ofapparatus for controlling a thermoregulation device 240, in accordancewith some applications of the present invention. Studies show thatdynamically regulating the temperature of a subject's sleep environmentmay improve the subject's sleep quality. For example, maintaining asteady temperature may increase the deep sleep (SWS) ratio, and coolingthe bed during REM may increase the REM sleep share rate. In someapplications, control unit 14 is connected to a thermoregulation device240 located, for example, in the subject's bed or elsewhere in thesubject's bedroom. Control unit 14 monitors the subject's sleep stagesand controls thermoregulation device 240 accordingly. Examples ofthermoregulation devices which may be configured to be controlled bycontrol unit 14 include air-conditioning units, electric heaters,radiators, bed coolers, and electric blankets.

Reference is now made to FIG. 12, which is a schematic illustration ofapparatus comprising a motion sensor 30, control unit 14, and alarmclock 212, in accordance with some applications of the presentinvention. For some applications, an alarm clock 212 is configured toreceive an output from control unit 14. The output is generated inresponse to a signal from motion sensor 30, and indicates whether aresting surface 37, e.g., a bed, is occupied by a subject. In responseto the output indicating that resting surface 37 is unoccupied, alarmclock 212 inhibits itself from sounding. This reduces the likelihood ofan alarm waking other members of the household, in cases where thesubject arose from resting surface 37 without taking measures to ensurethat the alarm would not subsequently begin or continue to sound. Insome applications, as shown in FIG. 12, alarm clock 212 and control unit14 are integrated into a common unit 213. In other applications, alarmclock 212 is separate from control unit 14, and communicates therewithby wired or wireless communication means.

In some cases, the individual might arise from bed at the sounding of analarm, but return to bed thereafter. Alternatively, the individual mightnot arise from bed, even though the alarm has sounded. In someapplications, alarm clock 212 is configured to sound after a delay, inresponse to the output from control unit 14 indicating that the bed isoccupied following a previous sounding of the alarm clock.

Reference is now made to FIG. 13, which is a schematic illustration of amotion sensor 30 powered by an external power supply 216 (i.e., a powersupply that is external to the motion sensor), and a rechargeablebattery 214, in accordance with some applications of the presentinvention. In some applications, motion sensor 30 may be powered by anexternal power supply 216, which draws current via a power cord 217connected to a wall outlet. Since some subjects are uncomfortable withpower being drawn from the wall and conveyed to a device which isunderneath them, motion sensor 30 is configured to not draw power frompower supply 216, in response to output from control unit 14 indicatingthat resting surface 37 is occupied by the subject. In someapplications, sensor 30 is configured to draw power from a rechargeablebattery 214, in response to the output indicating that resting surface37 is occupied. Rechargeable battery 214 is configured to draw powerfrom a power supply, e.g., power supply 216, in response to the outputfrom the control unit indicating that the resting surface is unoccupied,and to not draw power from the power supply, in response to the outputindicating that the resting surface is occupied.

In some applications, system 10 is configured to analyze sleep patternsof a subject and, in response thereto, produce a sleep report which canbe used, for example, for clinical sleep-study purposes.

In some applications, system 10 is configured to monitor subjects whoare generally healthy, in order to help the subjects maintain or improvetheir state of well-being. For example, system 10 may be configured tohelp a healthy subject avoid unhealthful conditions or improve sleepquality.

In some applications, system 10 is configured to be used in combinationwith home-based appliances. For example, system 10 may be configured totransmit a signal to a coffee-maker, the signal indicating that thesubject has woken up and/or has left the bed and might soon wish todrink a cup of coffee.

In some applications, a resting surface, e.g., a mattress, is configuredto be used with motion sensor 30, such that motion sensor 30 may bedisposed within the mattress. For example, the mattress may have anopening at its side configured to receive motion sensor 30, as well as areceptacle contained within the mattress configured to hold the sensor.Configuring a mattress in this manner allows for the sensor to bedisposed closer to the subject, relative to applications in which thesensor is disposed underneath the mattress.

In some applications, control unit 14 is configured to receivemattress-related parameters such as thickness and resilience, and toanalyze the signal from motion sensor 30 in light of the parameters. Themattress-related parameters may facilitate the quantification of signalamplitude on more of an absolute scale, thus facilitating a moreeffective response to the signal. For example, if the signal from sensor30 indicates a weak heartbeat, but the mattress is relatively thick andresilient, control unit 14 may withhold the output unit from generatingan alert.

Reference is made to FIGS. 1, 2, 4, and 16. In some applications,control unit 14 (e.g., via heartbeat pattern analysis module 23) isfurther configured to calculate an indication of aleft-ventricle-ejection-time (LVET) of subject 12. LVET is the time fromthe opening of the aortic valve during a heartbeat to the closing of theaortic valve during the heartbeat. A decrease in LVET may be indicativeof a clinical condition, such as hypovolemia and/or hemorrhaging, thatrequires immediate medical attention. Reference is made to FIG. 16,which is a schematic illustration of ballistocardiographic (BCG) signals300, 302, and 304 (in arbitrary units) used for calculating theindication of the LVET, in accordance with some applications of thepresent invention. Signal 300 is a heartbeat-related signal that isextracted by heartbeat pattern analysis module 23 from the raw motionsignal generated by sensor 30. Signal 300 is typically extracted bymeans of spectral filtering in the range of about 0.8 to about 5.0 Hz,as described hereinabove. (A matched filter may be used to extractsignal 302.) Signal 300 is typically smoothed by a low-pass filter toyield signal 302. (In FIG. 16, signal 300 is generally smooth, such thatsignal 302 appears substantially identical to signal 300.) Thederivative of signal 302 is calculated by module 23, after which thederivative is typically smoothed with a low-pass filter, yielding signal304. Each of signals 300, 302, and 304 is marked in FIG. 16 to show anindication of aortic valve openings (AO) and closings (AC). As describedabove, the time between these events is the LVET of the subject.

Heartbeat pattern analysis module 23 is configured to calculate anindication of the LVET by analyzing signal 304. (In some applications,the unsmoothed derivative of signal 302, instead of signal 304, isanalyzed.) For example, heartbeat pattern analysis module 23 may beconfigured to identify the most prominent positive peaks 308 in signal304. Following the identification of peaks 308, module 23 identifies thepositive peaks 306 that immediately precede peaks 308, which correspondto AO, and the negative peaks 310 that immediately follow peaks 308,which correspond to AC. As appropriate, techniques described in Alametsaet al, “Ballistocardiogaphic studies with acceleration andelectromechanical film sensors”, Medical Engineering & Physics, 2009,which is incorporated herein by reference, may be applied to calculatingthe LVET. The time between peaks 306 and 310, and/or another indicationof the LVET, is then calculated by module 23, and control unit 14 drivesan output device, e.g., user interface (U/I) 24, to generate an output,such as an audio and/or visual output, in response to the calculatedindication. Typically, calculating the indication involves averaging oneor more parameters, such as the time between peaks 306 and 310, overseveral heartbeats.

In some applications, control unit 14 (e.g., via module 23) is furtherconfigured to identify a risk of hypovolemia of the subject, in responseto the calculated indication of the LVET. For example, module 23 maydetermine that the LVET has decreased, relative to previously-calculatedLVETs and/or to a subject-baseline LVET or a population-baseline LVET,such that the subject is at risk of hypovolemia. For example, thesubject may be experiencing hypovolemia and/or hemorrhaging. Controlunit 14 drives U/I 24 to generate the output in response to theidentified risk of hypovolemia. Typically, the generated output includesan alert to a physician or other caregiver.

In some applications, control unit 14 (e.g., via module 23) is furtherconfigured to identify a change in stroke volume of subject 12.Typically, this is done by using the amplitude 312 of heartbeat signal302 as an indication of the subject's stroke volume, as amplitude 312 istypically positively correlated to stroke volume. Typically, whileamplitude 312 is being monitored by module 23, raw signal 300 is alsobeing processed by system 10 to identify any posture changes of thesubject. For example, the system may identify a posture change usingtechniques as described in US 2011/0112442 to Meger, which isincorporated herein by reference. If no posture change has beenidentified, a change in amplitude 312 is likely indicative of a changein stroke volume, since the change in amplitude cannot be attributed toa posture change of the subject. Control unit 14 drives the outputdevice (e.g., U/I 24) to generate an output, in response to theidentified change in stroke volume.

In some applications, the control unit is further configured to identifya risk of hypovolemia of the subject, in response to the identifiedchange in stroke volume. For example, the control unit may identify arisk of hypovolemia (e.g., of hemorrhaging), in response to the strokevolume dropping below a specified absolute or percentage threshold.Control unit 14 drives U/I 24 to generate the output in response to theidentified risk of hypovolemia. Typically, the generated output willinclude an alert to a physician or other caregiver. In someapplications, the risk of hypovolemia is identified in response to boththe change in stroke volume and a change in LVET. For example, a slightdecrease in stroke volume may be cause for alarm only if it isaccompanied by a decrease in LVET.

Reference is now made to FIG. 17, which is a schematic illustration ofapparatus for use with a plurality of sleeping subjects 314, inaccordance with some applications of the present invention. Theapparatus comprises at least one sensor 316 (e.g., at least two sensors316, e.g., exactly two sensors 316) configured to monitor each ofsubjects 314 while the subjects sleep. For example, as shown in FIG. 17,sensors 316 may comprise non-contact motion sensors 30, configured tosense motion of the subjects while the subjects sleep. (Typically, tohelp reduce contamination of the motion signal by motion of the othersubject, each sensor 30 is placed underneath the outer shoulder of thesubject being sensed.) Alternatively or additionally, sensors 316 maycomprise at least one sensor of another type, such as anelectromyographic sensor and/or an imaging sensor. In response to themonitoring, sensors 316 generate a respective signal for each of thesubjects. Control unit 14 is configured to analyze the signals, and,based on the analyzing, identify at least one sleep-related parameterfor each of the subjects. For example, for each of the subjects, thecontrol unit may be configured to identify one or more of the followingparameters:

(i) A length of time for which the subject has been sleeping, e.g., alength of time for which the subject has been in a deep sleep;

(ii) A number of prior awakenings of the subject, e.g., a number ofprior awakenings during the present sleeping period and/or during aprevious sleeping period;

(iii) A stage of a sleep cycle of the subject.

In identifying the sleep-related parameter(s), as well as generally, inidentifying that a person is sleeping and/or in identifying a sleepstage of the person (e.g., as described below with reference to numerousfigures), the control unit may use one or more of the techniquesdescribed in (a) US 2007/0118054 to Pinhas (now abandoned), (b) Shinaret al., Computers in Cardiology 2001; Vol. 28: 593-596, and (c) Shinar Zet al., “Identification of arousals using heart rate beat-to-beatvariability,” Sleep 21(3 Suppl):294 (1998), each of which isincorporated herein by reference.

At least in response to the identified sleep-related parameters, andtypically further in response to receiving an input from a second sensor318, control unit 14 identifies at least one of the subjects forwakening, and at least one of the subjects not for wakening. Typically,the apparatus further comprises a wakening device 324, and the controlunit is configured to drive wakening device 324 to wake the subject(s)identified for wakening.

A typical situation in which the described apparatus may be used isshown in FIG. 17. Two parents 314 of a baby 320 are sleeping on a bed37, while baby 320 sleeps in a different room. Second sensor 318comprises, for example, an audio sensor 322, configured to communicate(e.g., wirelessly) a signal to control unit 14 in response to soundsmade by baby 320. (In other applications, sensor 318 may comprise adifferent type of sensor, such as non-contact motion sensor 30 and/or animage sensor.) In response to receiving the input from sensor 318, thecontrol unit identifies that baby 320 is crying, such that one ofparents 314 should be wakened. Based on the sleep-related parameters,the control unit identifies the parent to be wakened. For example, ifone parent is in a deep sleep while the other is not, the latter may beidentified for wakening. Similarly, if one parent awoke in response tothe previous crying episode, the other parent may be wakened in responseto the current episode. In some applications, as shown in FIG. 17,wakening device 324 comprises a separate unit (e.g., a separatealarm-generating mechanism) for each of the sleeping subjects, such thatone subject can be woken with minimal disturbance to the other. In otherapplications, wakening device 324 comprises a single unit. For example,in some applications, wakening device 324 may be integrated with U/I 24(FIG. 2).

Although FIG. 17 shows two sensors 316, it is noted that the scope ofthe present invention includes the use of exactly one sensor 316 (e.g.,exactly one motion sensor 30) to monitor both subjects 314. It isfurther noted that the apparatus described with reference to FIG. 17 maybe used in combination with subject identification module 102 (FIG. 4),which helps differentiate between the motion of the first subject andthe motion of the second subject, and/or in combination with one or moreof the mechanical filtering applications described hereinabove. Forexample, sensor plate 140 with hardened edges 142 (FIG. 5), sensor plate238 with rigid edge region 227 (FIG. 9A), etc. may be used in order toreduce contamination of one subject's motion signal by the othersubject. Similarly, other “two-person” applications describedhereinbelow with reference to FIGS. 18, 20, 21, and 22 may be practicedin combination with subject identification module 102 and/or one or moreof the mechanical filtering applications described herein.

Other situations in which the described apparatus may be used include asituation in which a plurality (e.g., three or more) doctors or othercaregivers are sleeping in a room, e.g., a resting room in a hospital.Sensor 318 senses a physiological parameter of a patient, andcommunicates the parameter to the control unit. In this situation,sensor 318 typically comprises a “dedicated” physiological sensor, suchas an electrocardiograph, blood pressure monitor, etc., although sensor318 may also comprise a sensor of the type described above, e.g.,non-contact motion sensor 30. In response to the input from the sensor,the control unit determines that at least one, but not all, of thedoctors should be woken, in order to tend to the patient. Based on thesleep-related parameters, as described above with respect to the parentsof baby 320, the control unit identifies at least one of the doctors forwakening, and at least one of the doctors not for wakening. (In thissituation, subjects 314 will typically be sleeping on multiplerespective beds, and the apparatus may comprise more than one controlunit, e.g., one control unit per bed, in communication with each other.)

In some applications, the control unit is further configured to generatea report that shows a history of the at least one sleep-relatedparameter for each of the subjects. The report may be generated atregular intervals, such as after every night. The generation of such areport may be helpful in avoiding conflicts. For example, in theparenting situation described above, the parent who was woken may feelless resentful if the report shows that despite been woken to tend tothe crying baby, he/she slept better and/or longer overall, relative tothe other parent.

Reference is now made to FIG. 18, which is a schematic illustration ofapparatus for activating a medical device 326 (e.g., a continuouspositive airway pressure (CPAP) device) for a subject 12 who is sleepingin proximity to at least one other person 328, in accordance with someapplications of the present invention. The apparatus comprises at leastone sensor 316 (e.g., at least two sensors 316, e.g., exactly twosensors 316) configured to monitor subject 12 and person 328. Forexample, as shown in FIG. 18, sensors 316 may comprise non-contactmotion sensors 30, configured to sense motion of subject 12 and person328 while they sleep. Alternatively or additionally, sensors 316 maycomprise at least one sensor of another type, such as anelectromyographic sensor and/or an imaging sensor. In response to themonitoring, sensors 316 generate a respective signal for each of subject12 and person 328. Control unit 14 analyzes the signal for the subject,and, based on the analyzing, identifies at least one physiologicalparameter of the subject that relates to whether or not the deviceshould be activated. For example, the control unit may identify arespiration-related parameter of subject 12 that is indicative of anoccurring or expected episode of apnea, e.g., as described in US2013/0281866 to Shinar, which is incorporated herein by reference.Alternatively or additionally, the control unit may identify asleep-related parameter of subject 12 (e.g., how deeply the subject issleeping) that relates to whether or not the device should be activated.

If subject 12 were sleeping alone, the identification of thephysiological parameter might be sufficient cause to activate medicaldevice 326. For example, if subject 12 were sleeping alone, therespiration-related parameter predictive of an apnea episode might besufficient cause for the control unit to activate the CPAP device.However, given that subject 12 is not sleeping alone, the control unitalso analyzes the signal for the other person, identifies at least onesleep-related parameter of the other person based on the analyzing, andactivates the medical device further in response to the sleep-relatedparameter. For example, the sleep-related parameter may include a stageof sleep of the other person. If the other person is in a deep sleep,for example, the medical device may be activated, since the activationof the device is unlikely to disturb the other person. Conversely, ifthe other person is awake, the medical device may not be activated,since activation of the device may prevent the person from fallingasleep. (If the other person is in a light sleep, the medical device mayor may not be activated, depending on the application and possibly alsoon other factors, as further described immediately hereinbelow.) In someapplications, the sleep-related parameter includes an indication ofwhether the other person is trying to fall asleep, and the control unitis configured to activate (or not activate) the medical device based onthe indication. For example, if the parameter indicates that the otherperson is awake but is not trying to fall asleep (e.g. the other personis sitting in bed, and/or reading while lying in bed), the device may beactivated. Conversely, if the parameter indicates that the other personis trying to fall asleep (e.g., the person is lying in a sleepingposition) the device may not be activated. In some applications, anoverride feature is provided, whereby the medical device may beactivated regardless of the sleep-related parameter of the other person.

In some applications, the control unit identifies one or more otherfactors, and in response to those factors, activates (or does notactivate) the medical device. For example, in some applications, thecontrol unit is further configured, based on the analyzing of thesubject's signal, to identify a likelihood of an upcoming occurrence ofa clinical episode of the subject. For example, the control unit mayidentify that there is high chance that the subject will soon experiencean episode of apnea. In response to this likelihood, the control unitmay activate the CPAP device, even if the other person is likely to bedisturbed. In some applications, the control unit is further configuredto, based on the analyzing of the subject's signal, identify an expectedseverity of the upcoming occurrence, and to activate (or not activate)the medical device in response to the expected severity. For example, ifthe predicted apnea episode is expected to be severe, the control unitmay be configured to activate the medical device, even if the otherperson is likely to be disturbed.

In some applications, the control unit is configured to activate themedical device, further in response to an input that includes a historyof awakenings of the subject and/or of the other person in response toprevious activations of the medical device. For example, if the historyshows that the other person is typically woken when the device isactivated, the control unit may activate the device less readily, e.g.,only if the other person is in a deep sleep. In some applications, thecontrol unit is configured to track the history of awakenings of thesubject and/or of the other person, thus allowing the control unit tolearn the proper threshold to use when determining whether or not toactivate the device. In some applications, the control unit isconfigured to activate the medical device, further in response to aninput indicative of a sleep-disturbance tolerance of the subject, and/oran input indicative of a sleep-disturbance tolerance of the at least oneother person. This input may be received, for example, via U/I 24 (FIG.2). If the tolerance is low (i.e., if the input indicates that thesubject and/or the other person is a light sleeper), the control unitwill activate the device less readily.

In some applications, as shown in FIG. 18, the control unit is furtherconfigured to activate a noise-cancelation device 330 (e.g.,noise-canceling headphones) for the at least one other person, uponactivating the medical device. For example, if the control unit hasdetermined that the medical device should be activated, but the otherperson is likely to be disturbed by the activation of the device, thecontrol unit may activate the medical device while also activatingnoise-cancelation device 330.

Although FIG. 18 shows two sensors 316, it is noted that the scope ofthe present invention includes the use of exactly one sensor 316 (e.g.,exactly one motion sensor 30) to monitor both subject 12 and otherperson 328. In such applications, subject identification module 102(FIG. 4) may be used to differentiate between the motion of the subjectand the motion of the other person.

Reference is now made to FIG. 19, which is a schematic illustration ofapparatus 334 for use with a person 338 who is on a resting surface 37(e.g., a bed) and for use with an illuminator 332, in accordance withsome applications of the present invention. (Illuminator 332 may beintegrated with resting surface 37, as shown in FIG. 19, or disposed atthe side of the resting surface, e.g., on a night table.) Apparatus 334comprises a sensor 316 configured to monitor person 338 and generate asignal in response thereto. Sensor 316 may comprise, for example,non-contact motion sensor 30, configured to sense motion on restingsurface 37 and generate a motion signal in response thereto.Alternatively or additionally, sensor 316 may comprise at least onesensor of another type, such as an electromyographic sensor and/or animaging sensor.

Control unit 14 is configured to analyze the signal from the sensor,and, in response thereto, calculate a bed-exit likelihood, which is alikelihood that the person has left the resting surface and/or alikelihood that the person is preparing to leave the resting surface.(“Preparing to leave the resting surface” may be defined, for example,as “intending to leave the resting surface within a given period oftime, e.g., 2 minutes”) In response to the bed-exit likelihood, controlunit 14 selects an illumination intensity value from a set of at leastthree values, and sets an illumination intensity of illuminator 332 tothe selected illumination intensity value. For example, from a set of“high”, “low”, and “off”, control unit may select “high” in response toa relatively high likelihood, “low” in response to a lower likelihood,and “off” in response to a relatively low likelihood. (The set of“high”, “low”, and “off” is being used here as an example only. Inpractice, the set of values may contain any number of values that is atleast three.) The control unit sets the illumination intensity bysending a wired or wireless signal to the illuminator. (Similarly, withrespect to all descriptions herein of the control unit controlling adevice, e.g., the communication device, waking mechanism, etc. shown inany of FIGS. 20-23, it is noted that the control unit controls thedevice by sending a wired or wireless signal to the device.) Incalculating the likelihood that the person has left the resting surface,the control unit may, for example, use one or more of thebed-exit-detection techniques described in US 2013/0267791 to Halperin,which is incorporated herein by reference.

Typically, in response to analyzing the signal, control unit 14calculates a likelihood that the person is awake (e.g., using one ormore of the awakening-detection techniques described in US 2013/0267791to Halperin, which is incorporated herein by reference), and calculatesthe bed-exit likelihood in response thereto. For example, if the motionsignal from motion sensor 30 is indicative of the person being awake,the control unit may calculate a relatively high likelihood that theperson is awake, and, in response thereto, a relatively high likelihoodthat the person is preparing to leave the resting surface. Alternativelyor additionally, the control unit calculates a likelihood that theperson is sitting (e.g., using one or more of the techniques describedin US 2013/0267791 to Halperin, which is incorporated herein byreference), and calculates the bed-exit likelihood in response thereto.For example, the control unit may calculate a relatively high likelihoodthat the person is sitting, and, in response thereto, a relatively highlikelihood that the person is preparing to leave the resting surface.Alternatively or additionally, the control unit calculates asignal-to-noise ratio (SNR) of the signal (e.g., by using a real-timenoise estimator, and/or as described in US 2013/0267791 to Halperin,which is incorporated herein by reference), and calculates the bed-exitlikelihood in response thereto. Typically, a relatively highsignal-to-noise ratio is indicative that the person is in bed, whereas arelatively low signal-to-noise ratio is indicative that the person hasleft the bed. Therefore, the control unit typically calculates a higherbed-exit likelihood in response to calculating a first signal-to-noiseratio, relative to calculating a second signal-to-noise ratio that ishigher than the first signal-to-noise ratio.

In some applications, the control unit calculates both types of bed-exitlikelihood, i.e., both the likelihood that the person has left theresting surface, and the likelihood that the person is preparing toleave the resting surface. In response to the likelihood that the personhas left the resting surface, the control unit identifies a firstillumination intensity value from the set of values, and in response tothe likelihood that the person is preparing to leave the restingsurface, the control unit identifies a second illumination intensityvalue from the set of values. The control unit then selects a maximumvalue of the first illumination intensity value and the secondillumination intensity value, and sets the illumination intensity of theilluminator to the maximum value. For example, referring again to theset of “high”, “low”, and “off”, if there is a relatively low likelihoodthat the person has left the bed, such that the first selected value is“off”, but there is a relatively high likelihood that the person ispreparing to leave the bed, such that the second selected value is“high”, the control unit will set the illuminator to “high”.Alternatively, for example, if there is a relatively high likelihoodthat the person has left the bed, such that the first selected value is“high”, the control unit will set the illuminator to “high”, regardlessof the likelihood that the person is preparing to leave the bed.

Typically, control unit 14 selects the illumination intensity value byapplying to the bed-exit likelihood a function that is generallymonotonically increasing with respect to the bed-exit likelihood, andselecting the output of the function as the illumination intensityvalue. (In the context of the present application, a function that isgenerally monotonically increasing is a function for which at least 90%of the output values are not less than the preceding output value. Thesame definition applies to generally monotonically decreasing, mutatismutandis.) Typically, the control unit selects a zero illuminationintensity value (i.e., “off”), in response to the bed-exit likelihoodbeing less than a threshold. For example, the control unit may select a“high” intensity in response to likelihoods above 90%, a “low” intensityin response to likelihoods between 30% and 90%, and “off” in response tolikelihoods below 30%.

In some applications, the control unit selects the illuminationintensity value further in response to a time of day, a date, ageographical location, a sunrise time, and/or a sunset time. Forexample, if the person usually sleeps between 11 pm and 6 am, thecontrol unit may select a “high” intensity in response to a likelihoodof 90% at 7 am, but a “low” intensity in response to a likelihood of 90%at 3 am. Alternatively or additionally, apparatus 334 further comprisesan ambient light detector 336 configured to detect a level of ambientlight, and the control unit selects the illumination intensity valuefurther in response to the level of ambient light. For example, inresponse to a likelihood of 90%, the control unit may select a “high”intensity if there is a relatively low level of ambient light, but onlya “low” intensity if there is a relatively high level of ambient light.

In some applications, the control unit is further configured to, inresponse to the bed-exit likelihood and/or a time of day, select anillumination color value from a set of at least two color values, andset an illumination color of the illuminator to the selectedillumination color value. For example, the control unit may select a redcolor in response to a relatively low bed-exit likelihood, and a bluecolor in response to a relatively high bed-exit likelihood;alternatively or additionally, the control unit may select a red colorduring typical sleeping hours, and a blue color otherwise. For at leastsome people, red illumination is more conducive to sleep than is blueillumination. Thus, the selection of the red color during typicalsleeping hours, rather than the blue color, helps the person fall asleepupon returning to bed. Furthermore, the selection of the red color inresponse to a relatively low bed-exit likelihood helps minimize thedisturbance to the person in the event of a “false positive”, i.e., inthe event that the person is not actually preparing to leave the bed.

In some applications, control unit 14 is configured to identify a sleepstage of person 338. In such applications, the control unit mayascertain, in response to analyzing the signal, that person 338 is in alight sleep stage on the resting surface, and in response thereto, driveilluminator 332 to wake the person by illuminating. Waking the person inthis manner may be helpful, for example, if the person shares a bedand/or a room with a second person (as described hereinbelow withreference to FIG. 20), since an increase in illumination may be lessdisturbing to the second person than the sounding of an alarm. Since,however, the increase in illumination may be insufficient to wake person338 if (s)he is in a relatively deep sleep, illumination is used to wakethe person only if the person is in a light sleep stage.

Reference is now made to FIG. 20, which is a schematic illustration ofapparatus 334, in accordance with some applications of the presentinvention. In some applications, first person 338 shares a sleeping area(e.g., a bed, and/or a room) with a second person 340. In suchapplications, the control unit identifies a second-person-sleepinglikelihood, which is a likelihood that the second person is sleeping,and selects the illumination intensity value further in response to thesecond-person-sleeping likelihood. For example, in response to abed-exit likelihood of 90%, the control unit may select a “high”intensity if the second-person-sleeping likelihood is relatively low,but only a “low” intensity if the second-person-sleeping likelihood isrelatively high. Typically, the control unit applies to thesecond-person-sleeping likelihood a function that is generallymonotonically decreasing with respect to the second-person-sleepinglikelihood, and selects the output of the function as the illuminationintensity value. The control unit may apply a two-variable function to(a) the bed-exit likelihood and (b) the second-person-sleepinglikelihood, where the two-variable function is generally monotonicallyincreasing with respect to the bed-exit likelihood, and generallymonotonically decreasing with respect to the second-person-sleepinglikelihood. An example of such a function, for each of the two types ofbed-exit likelihood, is shown in the tables below. (For simplicity andease of illustration, the second-person-sleeping likelihood is shown ashaving one of only two values: “low”, and “high”, even though, inpractice, it can take on any number of values between 0 and 100%.)

TABLE 1 Lighting Intensity Likelihood that the first High second-person-Low second-person person has exited the bed sleeping likelihood sleepinglikelihood  0%  0%  0% 10%  0%  0% 20%  0%  10% 30% 10%  20% 40% 10% 30% 50% 20%  40% 60% 30%  40% 70% 50%  60% 80% 60%  80% 90% 80% 100%99% 80% 100%

TABLE 2 Lighting Intensity Likelihood that the first High second-person-Low second-person person has exited the bed sleeping likelihood sleepinglikelihood  0%  0%  0% 10%  0%  0% 20%  0%  0% 30%  0%  0% 40% 10%  0%50% 10% 10% 60% 20% 10% 70% 20% 10% 80% 20% 20% 90% 20% 20% 99% 30% 20%

As described hereinabove with reference to FIG. 19, the control unit mayselect two intensity values in response to, respectively, the two typesof bed-exit likelihood, and select the maximum of the two values as theilluminator intensity. For example, if the likelihood that the firstperson has exited the bed is 30%, the likelihood that the first personis preparing to exit the bed is 60%, and the second-person-sleepinglikelihood is “low”, the control unit may select (per Tables 2 and 3above) the maximum of a 20% intensity and a 10% intensity, which is 20%.

In some applications, the control unit selects a zero illuminationintensity value (i.e., an “off” value), in response to thesecond-person-sleeping likelihood exceeding a threshold. This selectionmay also be in response to other factors, e.g., the bed-exit likelihood.For example, if the bed-exit likelihood is relatively high, the controlunit may not select a zero illumination intensity value, even though thesecond-person-sleeping likelihood exceeds the threshold.

In some applications, a single sensor 316 senses the motion of bothpersons. This may be the case, for example, when the first and secondpersons share a bed, and a single motion sensor 30 is used to sensemotion on the bed. The control unit analyzes the motion signal from thesingle sensor, and calculates the second-person-sleeping likelihood inresponse thereto. (When a single motion sensor 30 is used, subjectidentification module 102 (FIG. 4) may be used to differentiate betweenthe motion of the first person and the motion of the second person.) Inother applications, such as the application shown in FIG. 20, a firstsensor 316 a (e.g., a first motion sensor 30 a) monitors first person338, while a second sensor 316 b (e.g., a second motion sensor 30 b)monitors second person 340. (The two persons may be on the same bed, oron different beds.) The control unit analyzes the signal (e.g., a motionsignal) from second sensor 316 b, and in response thereto, calculatesthe second-person-sleeping likelihood.

Alternatively or additionally, the control unit identifies thesecond-person-sleeping likelihood in response to a time of day. Forexample, if the second person usually sleeps between 11 pm and 6 am, thecontrol unit may identify a higher second-person-sleeping likelihoodbetween 11 pm and 6 am, relative to other times of the day.Alternatively or additionally, apparatus 334 further comprises an inputunit 342, and the control unit identifies the second-person-sleepinglikelihood in response to an input thereto. For example, the secondperson may use input unit 342 to indicate that (s)he is going to sleep,and the control unit will, in response to the input, begin to identify ahigher second-person-sleeping likelihood. Input unit 342 may be part ofuser interface (U/I) 24, described hereinabove with reference to FIG. 1,or may be a separate unit, such as the input unit of a mobile phone thatis in communication with the control unit.

In some applications, as shown in FIG. 20, apparatus 334 is for use withboth first illuminator 332 and a second illuminator 344, where theilluminators are located such that, when the first and second personsare on resting surface 37 (or on separate resting surfaces 37), firstilluminator 332 is closer to the first person than to the second person,and second illuminator 344 is closer to the second person than to thefirst person. The control unit is configured to set an illuminationintensity of the second illuminator to be different from theillumination intensity of the first illuminator, in response to (a) alikelihood that the second person has left resting surface 37, and/or alikelihood that the second person is preparing to leave resting surface37 (i.e., the bed-exit likelihood for the second person), and (b) alikelihood that the first person is sleeping (i.e., afirst-person-sleeping likelihood).

Reference is now made to FIG. 21, which is a schematic illustration ofapparatus 346 for use with a waking mechanism 348 (e.g., an alarm clock,a mobile phone, an illuminator, and/or a vibrating element) thatexecutes a waking routine to wake a subject 12 (e.g., first person 338)who is sleeping near second person 340, in accordance with someapplications of the present invention. Apparatus 346 comprises a sensor316, configured to monitor second person 340 and generate a signal inresponse thereto. Sensor 316 may comprise, for example, motion sensor30, configured to sense motion on the resting surface 37 on which thesecond person is resting and generate a motion signal in responsethereto. Alternatively or additionally, sensor 316 may comprise at leastone sensor of another type, such as an electromyographic sensor and/oran imaging sensor.

Prior to execution of the waking routine, control unit 14 analyzes thesignal from sensor 316. In response to analyzing the signal, the controlunit identifies a likelihood that the second person is sleeping, and inresponse to the likelihood, sets an intensity of the waking routine bysending a signal to the waking mechanism. For example, in response to arelatively high likelihood, the control unit will set the intensity ofthe waking routine (e.g., the volume of an alarm) to be relatively low,so as to reduce disturbance to the second person. Following thebeginning of the execution of the waking routine, the control unitanalyzes the signal. If, in response to analyzing the signal, thecontrol unit identifies that the subject has not woken, the control unitincreases the intensity of the waking routine, e.g., increases thevolume of an alarm. These steps may be repeated several times, until thecontrol unit identifies that the subject has woken. In this manner, thechances of waking the second person are reduced. Alternatively oradditionally, in response to a relatively high likelihood that thesecond person is sleeping, the control unit may activate an alternatewaking mechanism that is less potentially disturbing to the secondperson, such as an illuminator (FIG. 20).

In some applications, control unit 14 further identifies a sleep stageof the second person, and sets the intensity of the waking routine inresponse to the identified sleep stage. For example, if the secondperson is in a deep sleep, and therefore less likely to be disturbed bythe waking routine, the control unit may set the waking routine to arelatively high intensity.

FIG. 21 also shows apparatus 376 for use with a communication device 378belonging to a first person 338, in accordance with some applications ofthe present invention. (It is noted that communication device 378 may beidentical to waking mechanism 348.) Communication device 378 generatesan alert upon receiving an incoming communication; for example,communication device 378 may include a mobile phone that rings uponreceiving an incoming call.

In response to analyzing the signal from sensor 316, the control unitidentifies a likelihood that the second person is sleeping, and controlsan intensity of the alert in response to the identified likelihood. Forexample, in response to identifying that there is a relatively highlikelihood that the second person is sleeping, the control unit maylower the intensity of the alert (e.g., lower the volume of the ring),or inhibit the communication device from activating the alert (e.g.,mute the phone). In some applications, the control unit continuallyidentifies the likelihood that the second person is sleeping, andcontinually controls the communication device in response thereto. (Forexample, the control unit may continually adjust the volume of theringer of the phone, regardless of whether there is an incoming call.)In other applications, the control unit controls the intensity of thealert further in response to the communication device receiving theincoming communication, e.g., the control unit adjusts the volume of theringer only upon the phone receiving an incoming call.

In some applications, the control unit controls the intensity of thealert in response to the identified sleep stage of second person 340.For example, if the second person is sleeping lightly (and is thereforerelatively likely to be disturbed by the alert), the control unit maylower the volume of the ring more than if the second person weresleeping deeply or were awake.

FIG. 21 also shows apparatus 386 for use with a mechanism 388 (e.g., atoilet-flushing mechanism a window-opening mechanism) that is activatedby a first person 338, in accordance with some applications of thepresent invention. In response to analyzing the signal from sensor 316(e.g., motion sensor 30), the control unit identifies a likelihood thatthe second person is sleeping, and delays the activation of themechanism, and/or inhibits (e.g., prevents) the activation of themechanism, in response to the identified likelihood. For example, if thecontrol unit identifies a high likelihood that second person 340 issleeping, the control unit may delay the flushing of the toilet untilthe likelihood is reduced. (This may be effected, for example, bycommunicating a signal to a “smart” toilet flusher of the toilet.) Insome applications, the control unit further identifies a sleep stage ofthe second person, and delays the activation of the mechanism inresponse to the identified sleep stage. For example, the flushing of thetoilet may be delayed if the second person is sleeping lightly, but notif the second person is sleeping deeply or is awake.

In order to reduce contamination of the motion signal from second person340, the applications shown in FIG. 21 may be practiced in combinationwith subject identification module 102 (FIG. 4), and/or in combinationwith mechanical filtering provided by, for example, sensor plate 140with hardened edges 142 (FIG. 5), sensor plate 238 with rigid edgeregion 227 (FIG. 9A), etc., as described hereinabove.

Reference is now made to FIG. 22, which is a schematic illustration ofapparatus 350 for use with a waking mechanism 348 (e.g., an alarm clock,a mobile phone, an illuminator, and/or a vibrating element) thatexecutes a waking routine to wake a subject 12 (e.g., a first person338) who is on a resting surface 37, in accordance with someapplications of the present invention. Apparatus 350 comprises a sensor316, configured to monitor subject 12 and generate a signal in responsethereto. Sensor 316 may comprise, for example, non-contact motion sensor30, configured to sense motion on the resting surface 37 on which thesubject is resting and generate a motion signal in response thereto.Alternatively or additionally, sensor 316 may comprise at least onesensor of another type, such as an electromyographic sensor and/or animaging sensor. Prior to execution of the waking routine, control unit14 analyzes the signal from the sensor. If the control unit identifies,in response to the analyzing, that the subject is not on the restingsurface, the control unit inhibits waking mechanism 348 from executingthe waking routine.

In some applications, control unit 14 is further configured to identifya likelihood that a second person 340 is sleeping near the subject, andset an intensity of the waking routine in response to the likelihood bysending a signal to the waking mechanism. Generally, this is done asdescribed hereinabove with reference to FIG. 21; for example, thecontrol unit may increase the intensity of the waking routine one ormore times, until the subject is woken. Furthermore, in someapplications, the control unit changes an angle of the resting surface(e.g., as described in US 2013/0267791 to Halperin, which isincorporated herein by reference), in response to identifying that thewaking routine has not woken the subject. The change in angle of theresting surface may facilitate the waking of the subject, while causingonly a relatively small disturbance to other individuals in the area,e.g., second person 340. In some applications, the control unitidentifies a sleep stage of the subject, and changes the angle of theresting surface in response to the identified sleep stage. For example,if the subject is in a deep sleep, the control unit may change the angleby a relatively large amount, such as to increase the probability thatthe subject will wake up.

In some applications, if control unit 14 identifies, in response toanalyzing the signal following the beginning of execution of the wakingroutine, that the subject has woken, the control unit changes the angleof the resting surface. For example, the control unit may move the upperportion of the bed to a more upright position, in order to facilitatethe subject's exit from bed.

Although FIG. 22 shows two sensors 316, it is noted that the scope ofthe present invention includes the use of exactly one sensor 316 (e.g.,exactly one motion sensor 30) to monitor both first person 338 andsecond person 340. In such applications, subject identification module102 (FIG. 4) may be used to differentiate between the motion of thefirst person and the motion of the second person.

Reference is now made to FIG. 23, which is a schematic illustration ofapparatus 352 for use with (i) a waking mechanism 348 that executes awaking routine to wake a subject 12 who is on a resting surface 37, and(ii) an output unit 354, in accordance with some applications of thepresent invention. (In some applications, as shown in FIG. 23, a singledevice, such as a mobile phone, may include both waking mechanism 348and output unit 354.) Apparatus 350 comprises a sensor 316, configuredto monitor subject 12 and generate a signal in response thereto. Sensor316 may comprise, for example, motion sensor 30, configured to sensemotion on the resting surface 37 on which the subject is resting andgenerate a motion signal in response thereto. Alternatively oradditionally, sensor 316 may comprise at least one sensor of anothertype, such as an electromyographic sensor and/or an imaging sensor.

Prior to execution of the waking routine, control unit 14 analyzes thesignal from sensor 316, and, in response to analyzing the signal,identifies a sleep stage of the subject. Upon the subject waking, thecontrol unit drives output unit 354 to output the identified sleep stageto the subject, only if the identified sleep stage is a slow-wave (i.e.,deep) sleep stage. (The output may include a technical description ofthe sleep stage, e.g., “NREM stage 3”, and/or a non-technicaldescription, e.g., “deep sleep”.) Alternatively or additionally, thecontrol unit drives output unit 354 to output a recommendation to thesubject to perform a wakefulness-inducing activity, only if theidentified sleep stage is a slow-wave sleep stage. For example, thecontrol unit may drive the output unit to output an audio and/or visualmessage such as “You were just woken from a deep sleep. Consider doingsome light exercise, or drinking a coffee.” Alternatively oradditionally, the control unit drives the output unit to output arecommendation to the subject to refrain from operating a vehicle for aspecific period of time, only if the identified sleep stage is aslow-wave sleep stage.

In some applications, in response to analyzing the signal prior to theexecution of the waking routine, the control unit identifies at leastone physiological parameter of the subject, such as the subject's heartrate, heart rate variability, respiration rate, respiration ratevariability, and/or blood pressure. The control unit then drives theoutput unit to output the physiological parameter, upon the subjectwaking. In some applications, the control unit drives the output unit tooutput the physiological parameter, only if the physiological parameterdeviates from a baseline value. The output of the physiologicalparameter may help the subject manage his/her post-waking activities.For example, if the subject sees that his/her heart rate is relativelyhigh, the subject may refrain from drinking coffee. In someapplications, in response to the physiological parameter deviating fromthe baseline value, the control unit drives the output unit to output arecommendation to the subject to perform a specific activity (e.g.,exercise), and/or a recommendation to refrain from performing a specificactivity (e.g., drinking coffee).

FIG. 23 also shows apparatus 380 for use with communication device 378(e.g., a mobile phone). In response to analyzing the signal from sensor316 (e.g., motion sensor 30), control unit 14 identifies a sleep stageof subject 12, and controls an intensity of the alert that is generatedby communication device 378 in response to the identified sleep stage.In some applications, the control unit lowers the intensity of the alertin response to a relatively light sleep stage, relative to a deepersleep stage. For example, the subject may indicate before going to sleepthat (s)he wishes to be woken upon receiving a call, but in a mannerthat generally minimizes potential disturbances to others. By providingfor an alert intensity that is generally increasing with the deepness ofthe subject's sleep, the control unit generally provides for the ringvolume to be loud enough to wake the subject up, but not significantlylouder than necessary. In other applications, the control unit controlsthe intensity in the opposite manner, i.e., it raises the intensity ofthe alert in response to a relatively light sleep stage, relative to adeeper sleep stage. (For example, the control unit may inhibit thecommunication device from activating the alert, in response to theidentified sleep stage being a slow-wave sleep stage, but allow thealert to be activated in response to a light sleep stage.) This behaviormay be in response to the subject indicating before going to sleep that(s)he does not wish to be woken from a deep sleep, but does not mindbeing woken from a light sleep.

In some applications, as described hereinabove with reference to FIG.21, the control unit controls the intensity of the alert further inresponse to the communication device receiving the incomingcommunication. In some applications, apparatus 380 further includeselements of apparatus 376, described hereinabove with reference to FIG.21. For example, the control unit may be further configured to identifya likelihood that a second person 340 (FIG. 21) is sleeping near thesubject, and control the intensity of the alert, further in response tothe likelihood.

FIG. 23 also shows apparatus 382 for inhibiting outgoing communicationfrom communication device 378 (e.g., a mobile phone). In response toanalyzing the signal from sensor 316 (e.g., motion sensor 30), controlunit 14 identifies that the subject is sleeping, and, in responsethereto, inhibits (e.g., prevents) outgoing communication from thecommunication device. By doing so, the control unit may at leastpartially prevent “sleeptexting” by subject 12, and/or may at leastpartially prevent another user (e.g., a mischievous child) from usingthe subject's device without the subject's permission. In inhibiting theoutgoing communication, the control unit may at least partially disablethe communication device (e.g., disable the texting and/or callingfunctionality of a mobile phone). In some applications, the control unitdrives the communication device to prompt the user to input an answer toan objective question (e.g., “What is the capital of Kansas?”), andallows outgoing communication from the communication device only if theanswer is correct. In this manner, outgoing communication from asleeping subject 12 (e.g., “sleeptexting”) may be at least partiallyprevented.

FIG. 23 also shows apparatus 384 for use with a subject 12 who is on aresting surface 37, in accordance with some applications of the presentinvention. In response to analyzing the signal from sensor 316 (e.g.,motion sensor 30), the control unit identifies a likelihood that thesubject has left the resting surface, and/or a likelihood that thesubject is preparing to leave the resting surface. In response to thelikelihood(s), and in response to the control unit further identifyingthat the subject is sleeping, the control unit generates a“sleepwalking” alert. For example, if the signal gave no indication thatthe subject woke prior to the indication that the subject left the bed,an alert will be generated. In response to the alert, a caregiver maycome to the subject's aid.

Reference is now made to FIG. 24, which is a schematic illustration ofapparatus 356 for identifying a posture of a subject 12, in accordancewith some applications of the present invention. Apparatus 356 comprisesa single motion sensor 30, configured to sense motion of a person (e.g.,the subject, or any other person) without contacting or viewing theperson or clothes the person is wearing, and generate a motion signal inresponse thereto.

During a learning stage 357, a person adopts a number of different lyingpostures at respective times, while being monitored by motion sensor 30.Control unit 14 receives a plurality of inputs indicative of postures ofthe person at the respective times. For example, for each posture thatthe person adopts, the control unit may receive an input that describes(or “classifies”) the posture, e.g., “supine”, “prone”, etc. By usingthe plurality of inputs and by analyzing the motion signal at therespective times, the control unit learns a posture-identificationtechnique. For example, the control unit may identify various featuresof the motion signal, such as amplitude, dominant frequencies, etc. thatdiscriminate between the various postures. Then, during an operativestage 359 that follows learning stage 357, when the subject is lying onresting surface 37 (e.g., a hospital bed) and being monitored by sensor30, the control unit uses the learned posture-identification techniqueto identify the posture of the subject. For example, by analyzing themotion signal, the control unit may identify particular features of thesignal that, during the learning stage, were found to be indicative of aparticular posture. The control unit then identifies that particularposture as being the posture of the subject.

Preferably, in order to improve the efficacy of the learnedposture-identification technique, learning stage 357 is performed withthe subject lying on resting surface 37, rather than with a differentperson and/or a different resting surface. However, in some applications(e.g., when the physical condition of subject 12 does not allow for thesubject to participate in the learning stage), control unit 14 uses amore “generic” posture-identification technique that was learned (e.g.,by the control unit) from one or more other persons lying on the same,or a different, resting surface. In using this technique, the controlunit may make use of parameters relating to the subject's physicalcondition (e.g., the subject's body mass index), and/or the restingsurface (e.g., a thickness of a mattress), in order to more effectivelyperform the posture identification.

In some applications, the control unit is further configured to verifycompliance of a healthcare provider for the subject with apressure-ulcer-prevention protocol, in response to identifying theposture.

Reference is now made to FIG. 25, which is a schematic illustration ofapparatus 358 for monitoring a subject 12, in accordance with someapplications of the present invention. Apparatus 358 comprises a motionsensor 30, configured to sense motion of the subject on resting surface37 and generate a motion signal in response thereto. Control unit 14analyzes the motion signal (analysis step 361), and, in responsethereto, identifies that the subject has lain on the resting surface(first identification step 363). Subsequently to the subject lying onthe resting surface, the control unit identifies a physiologicalparameter relating to a physiological slowing time of the subject(second identification step 365). For example, the control unit mayidentify a parameter relating to a slowing of a heart rate of thesubject, such as the time for the heart rate to slow to a normal restingvalue. Alternatively or additionally, the control unit may identify aparameter relating to a slowing of a respiratory rate of the subject,such as the time for the respiratory rate to slow to a normal restingvalue. If the control unit identifies that the physiological parametermay be indicative of a physiological deterioration of the subject, thecontrol unit generates an output (output generation step 367).

In some applications, the control unit identifies that the physiologicalparameter may be indicative of a physiological deterioration of thesubject by identifying that the physiological parameter deviates from abaseline value. For example, if, in a healthy person, the heart rategenerally slows to a normal resting value within 1-5 minutes, but thesubject's heart rate slowed to a normal resting value within more than10 minutes (or did not slow to a normal resting value at all, within agiven period of time), the control unit generates an output, e.g., awarning to a physician. The baseline may be with reference to thesubject, rather than with reference to a healthy person. For example,the baseline heart-rate slowing time may be the average slowing time forthe subject during the previous 7 days. In some applications, thecontrol unit is further configured to calculate the baseline value byanalyzing the motion signal following each of a plurality of instancesof a person (e.g., any healthy person, or the subject) lying on aresting surface.

Alternatively or additionally, the control unit identifies that thephysiological parameter may be indicative of a physiologicaldeterioration of the subject by identifying a deteriorating trend in thephysiological parameter. For example, if, over the last several days,the heart-rate slowing time of the subject has been steadily increasing,the control unit may identify this as a deteriorating trend, and maygenerate an output, e.g., a warning, in response thereto.

In some applications, the control unit identifies a possiblephysiological condition of the subject, in response to identifying thatthe physiological parameter may be indicative of a physiologicaldeterioration of the subject, and generates an output in responsethereto. For example, (a) in response to a deteriorating (e.g.,increasing) trend in heart-rate slowing time, and/or a heart-rateslowing time that deviates from (e.g., is greater than) a baselinevalue, the control unit may identify that the subject possibly suffersfrom clinical anxiety, or (b) in response to a deteriorating (e.g.,increasing) trend in respiratory-rate slowing time, and/or arespiratory-rate slowing time that deviates from (e.g., is greater than)a baseline value, the control unit may identify that the subjectpossibly suffers from asthma. In some applications, the control unitidentifies an activity level of the subject, in response to analyzingthe motion signal, and regulates the output in response to theidentified activity level. Typically, the control unit regulates theoutput by generating the output only if an adjusted physiologicalparameter deviates from the baseline value, or if the physiologicalparameter deviates from an adjusted baseline value. For example, inresponse to identifying a relatively high activity level, the controlunit may adjust a baseline heart-rate slowing time of 5 minutes to 7minutes, and hence, may not generate the output unless the heart-rateslowing time of the subject exceeds 7 minutes. Alternatively oradditionally, the control unit withholds generating the output if theidentified activity level is greater than a threshold, and/or does notbegin measuring the slowing time until the activity level of the subjectfalls below a threshold. By regulating the output in this manner, thecontrol unit may at least partially avoid generating false alarms.

Reference is now made to FIG. 26, which is a schematic illustration ofapparatus 360 for monitoring a subject (e.g., subject 12), in accordancewith some applications of the present invention. Apparatus 360 comprisesa sensor plate 362 comprising an upper surface 364 that is configured todeflect in response to motion of the subject. Apparatus 360 alsocomprises a sensor 366, such as a ceramic piezoelectric sensor,vibration sensor, pressure sensor, or strain sensor disposed underneathupper surface 364. Sensor 366 generates a motion signal in response tothe deflection of upper surface 364, and control unit 14 analyzes themotion signal and generates an output indicative of a condition of thesubject, in response thereto. Motion sensor 30, described throughout thepresent application, may comprise sensor plate 362 and sensor 366.

Center 368 of sensor 366 is typically disposed at a distance D from acenter 370 of sensor plate 362 that is at least 30% and/or less than70%, e.g., between 30% and 70%, of a length L of a line 372 drawn fromcenter 370 of the sensor plate to a perimeter 374 of the sensor plate,through center 368 of the sensor. (In this context, the “center” of thesensor is the centroid of a surface of the sensor, and similarly, the“center” of the sensor plate is the centroid of a surface of the sensorplate.) Generally, the disposition of sensor 366 in this manner isadvantageous in at least two ways:

(i) The sensor is more sensitive to deflections of the sensor plate atfrequencies between 1 and 100 Hz, relative to if the sensor weredisposed more toward the center or the perimeter of the sensor plate.The range of 1-100 Hz is significant, at least in that heartbeat-relatedsignals and, to a lesser extent, respiratory-related signals from thesubject include harmonic frequencies of interest that are within thisrange. (These harmonic frequencies may be used, for example, to predicta physiological condition of the subject, as described in U.S. Pat. No.8,679,034, which is incorporated herein by reference.) The greatersensitivity to the aforementioned range of frequencies is due at leastto (a) the asymmetric configuration of the sensor and sensor plate, and(b) the relative stiffness of upper surface 364 at the location at whichsensor 366 is disposed.

(ii) For cases in which subject 12 shares a bed with a partner, sensorplate 362 may be placed underneath the subject such that sensor 366faces toward the near edge of the bed, i.e., away from the partner. Inthis manner, sensor 366 will be less affected by signals from thepartner, relative to if it were disposed closer to the center of thesensor plate. In this regard, it is noted that sensor plate 362 may alsoinclude elements of sensor plate 238, described hereinabove withreference to FIGS. 9A-B and 10A-D. For example, sensor plate 362 mayinclude noise filter plate 226 (FIG. 9B), which, as describedhereinabove, allows for mechanical filtering of signals coming from thepartner. Alternatively or additionally, for example, sensor plate 362may include a slot 219 (as shown in FIG. 26), for improved sensing ofthe subject's signal and filtering of the partner's signal, as describedhereinabove with reference to FIG. 10C.

Typically, the upper surface area A2 of the sensor is between 0.2 and 30cm². (FIG. 25 shows the lower surface area of the sensor, which istypically very close or identical to the upper surface area.) Furthertypically, the upper surface area A1 of the sensor plate is between 20and 200 cm² or between 200 and 710 cm². In some applications, uppersurface area A1 of the sensor plate is between 2 and 8 times greater, orbetween 8 and 30 times greater, than upper surface area A2 of thesensor.

Reference is now made to (a) FIG. 27A, which is a schematic illustrationof apparatus 600 comprising motion sensor 30, a mains-power-connectiondevice 602, and control unit 14, and (b) FIG. 27B, which is a schematicillustration of mains-power-connection device 602, in accordance withsome applications of the present invention. Mains-power-connectiondevice 602 comprises electrically-conductive protrusions (e.g., prongs)604 that are configured to fit into holes in an electric socket. Themains-power-connection device receives electricity throughelectrically-conductive protrusions 604, and uses the electricity todeliver power to motion sensor 30. Control unit 14 is disposed withinthe mains-power-connection device such that, whenever the protrusionsare placed inside the holes, the control unit is at least partiallywithin 20 cm of the electric socket. For example, the control unit maybe at least partially within 10 cm of the electric socket, i.e.,distance D2 in FIG. 27A is less than 10 cm. As shown in FIG. 27B,mains-power-connection device 602 typically comprises a rigid housing606, from which the electrically-conductive protrusions protrude, andinside of which the control unit is disposed. In general, thedisposition of control unit 14 within mains-power-connection device 602is advantageous, especially in a home setting, in that it is lessnoticeable to an observer that the patient/subject is being monitored.Typically, control unit 14 communicates wirelessly with a server, and/orwith a mobile electronic device. For example, output from the controlunit may be communicated to a physician's mobile electronic device.

Reference is now made to FIGS. 28 and 29, which are schematicillustrations of apparatus 420 for use with a burglar alarm 422, inaccordance with some applications of the present invention. Burglaralarm 422 includes a detector 424 (e.g., a motion detector) configuredto detect activity (e.g., motion) and to generate an activity-detectionsignal in response thereto. Apparatus 420 comprises a sensor 316 (e.g.,motion sensor 30), and control unit 14. Control unit 14 identifies acorrespondence between (a) the activity-detection signal, and (b) thesignal that is generated by sensor 30, and inhibits burglar alarm 422from being triggered, in response to the correspondence. For example, ifa person 426 is moving on resting surface 37, sensor 30 will generate asignal indicative of the movement. If this signal corresponds to theactivity-detection signal of detector 424, e.g., detector 424 detectsactivity on resting surface 37, control unit 14 inhibits the burglaralarm from being triggered. On the other hand, the burglar alarm willnot be inhibited if the two signals don't correspond, e.g., it can beinferred that detector 424 is detecting activity outside of restingsurface 37. Another example is shown in FIG. 28. In FIG. 28, person 426is shown as having left resting surface 37. In response to analyzing thesignal from sensor 30, the control unit ascertains that the person hasleft the resting surface, and in response thereto, inhibits the burglaralarm from being triggered, since it is likely that the detector isdetecting activity of person 426.

In some applications, the control unit inhibits the burglar alarm frombeing triggered at a given time only if the person left the restingsurface more than a threshold amount of time prior to the given time.For example, as shown in FIG. 29, detector 424 may be disposed outsideof the bedroom, e.g., near the entrance to the house, and it typicallytakes a threshold amount of time for the person to walk from the bedroomto the area in which the detector is disposed. If the threshold amountof time has not passed, it is likely that detector 424 is detectingactivity of an entity other than person 426. The threshold amount oftime is typically an input to the control unit, and is typically afunction of the speed at which person 426 typically moves. In someapplications, burglar alarm 422 includes a motion-detection-based alarm,i.e., burglar alarm 422 includes motion detector 424, and the controlunit inhibits the motion-detection-based alarm. In some applications,burglar alarm 422 also includes a perimeter alarm 428, and the controlunit is configured to not inhibit perimeter alarm 428 from beingtriggered, while inhibiting the motion-detection-based alarm from beingtriggered.

Reference is now made to FIG. 30, which is a schematic illustration ofapparatus 430 for use with burglar alarm 422, in accordance with someapplications of the present invention. Apparatus 430 comprises sensor316 (e.g., motion sensor 30), and control unit 14. Control unit 14analyzes the signal from sensor 316. In response to the analyzing, thecontrol unit ascertains that person 426 is on the resting surface, andin response thereto, places burglar alarm 422 in an armed state. Ingeneral, apparatus 430 may comprise more than one sensor, and/or morethan one control unit. For example, FIG. 30 shows an application inwhich respective sensors and control units are disposed in respectiverooms. In response to the control units ascertaining that all of theresting surfaces are occupied, burglar alarm 422 is placed in an armedstate.

The arming of burglar alarm 422, as described hereinabove, is but anexample of many related actions that control unit 14 can perform (e.g.,via wireless communication), upon ascertaining that a person, or all ofthe persons in the household, is/are likely to be going to sleep. Forexample, control unit 14 may lock a door 432, reduce an intensity of(e.g., turn off) a light 434, turn off a device 436, and/or turn off anappliance 438. Alternatively or additionally, control unit 14 maygenerate a notification that (a) door 432 is unlocked, (b) light 434 ison, (c) device 436 is on, and/or (d) appliance 438 is on.

In general, control unit 14 may be embodied as a single control unit 14,or a cooperatively networked or clustered set of control units. Controlunit 14 is typically a programmed digital computing device comprising acentral processing unit (CPU), random access memory (RAM), non-volatilesecondary storage, such as a hard drive or CD ROM drive, networkinterfaces, and/or peripheral devices. Program code, including softwareprograms, and data are loaded into the RAM for execution and processingby the CPU and results are generated for display, output, transmittal,or storage, as is known in the art. Typically, control unit 14 isconnected to one or more sensors via one or more wired or wirelessconnections. Control unit 14 is typically configured to receive signals(e.g., motions signals) from the one or more sensors, and to processthese signals as described herein. In the context of the claims andspecification of the present application, the term “motion signal” isused to denote any signal that is generated by a sensor, upon the sensorsensing motion. Such motion may include, for example, respiratorymotion, cardiac motion, or other body motion, e.g., large body-movement.Similarly, the term “motion sensor” is used to denote any sensor thatsenses motion, including the types of motion delineated above.

Techniques described herein may be practiced in combination withtechniques described in one or more of the following patents and patentapplications, which are incorporated herein by reference. In someapplications, techniques and apparatus described in one or more of thefollowing applications are combined with techniques and apparatusdescribed herein:

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It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather, the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove, as well as variations and modifications thereofthat are not in the prior art, which would occur to persons skilled inthe art upon reading the foregoing description.

1. Apparatus for use with a subject who is a first person, who shares abed with a second person, the apparatus comprising: a thin, flat motionsensor configured to be placed underneath a portion of the bed, and,while disposed underneath the portion of the bed, to: detect motion ofthe subject without contacting the subject, without contacting clothesthe subject is wearing, without viewing the subject, and without viewingclothes the subject is wearing, detect motion of the second personwithout contacting the second person, without contacting clothes thesecond person is wearing, without viewing the second person, and withoutviewing clothes the second person is wearing, and generate a motionsignal in response to detecting motion of the subject and motion of thesecond person; and a control unit configured to: identify components ofthe motion signal that were generated in response to motion of thesubject, by distinguishing between components of the motion signal thatwere generated in response to motion of the subject, and components ofthe motion signal that were generated in response to motion of thesecond person, analyze the components of the motion signal that weregenerated in response to motion of the subject, and generate an outputin response thereto.
 2. The apparatus according to claim 1, wherein thecontrol unit is configured to identify components of the motion signalthat were generated in response to motion of the subject, by identifyingcomponents of the motion signal that have a signal strength that is acharacteristic signal strength of a motion signal of the subject.
 3. Theapparatus according to claim 1, wherein the control unit is configuredto identify components of the motion signal that were generated inresponse to motion of the subject by identifying components of themotion signal that have a pattern that is a characteristic pattern ofmotion of the subject.
 4. The apparatus according to claim 1, furthercomprising a weight sensor that is configured to detect when the subjectis lying above the motion sensor, wherein the control unit is configuredto identify the components of the motion signal that were generated inresponse to motion of the subject, in response to a signal that isgenerated by the weight sensor.
 5. The apparatus according to claim 1,wherein the motion sensor is configured to facilitate the identificationof components of the motion signal that were generated in response tomotion of the subject, by strengthening a signal strength of thecomponents of the motion signal that are generated in response to motionof the subject.
 6. The apparatus according to claim 5, wherein theapparatus is for use with a subject who lies on a mattress, and whereinthe sensor is configured to be placed at a position selected from thegroup consisting of: underneath the mattress at a position that ishigher than a head of the subject is typically placed, and adjacent toand in contact with a side of the mattress.
 7. The apparatus accordingto claim 6, wherein the sensor is configured such as to facilitateidentification, by the control unit, of components of the motion signalthat were generated in response to a longitudinal cardio-ballisticeffect of the subject.
 8. The apparatus according to claim 1, whereinthe control unit is configured to identify components of the motionsignal that were generated in response to respiratory motion of thesubject.
 9. The apparatus according to claim 1, wherein the control unitis configured to identify components of the motion signal that weregenerated in response to cardiac motion of the subject.
 10. Theapparatus according to claim 1, wherein the control unit is configuredto identify components of the motion signal that were generated inresponse to large body-movement of the subject.
 11. The apparatusaccording to claim 1, wherein the control unit is further configured to:analyze the motion signal, in response thereto, identify an effect oflarge body-movement of the second person on sleep of the subject, and inresponse thereto, generate a sleep-disturbance output.
 12. The apparatusaccording to claim 11, wherein: (A) the sleep-disturbance outputincludes an assessment of an effectiveness of a parameter at reducingthe effect of the large body-movement of the second person on the sleepof the subject, the control unit being configured to generate theassessment of the effectiveness of the parameter, and (B) the parameteris selected from the group consisting of: a parameter of a mattress onwhich the subject is sleeping, a parameter of the bed, a sleepingarrangement of the subject and the second person, and a room-environmentparameter, the control unit being configured to generate the assessmentof the effectiveness of the selected parameter.
 13. The apparatusaccording to claim 11, wherein: (A) the sleep-disturbance outputincludes a recommendation to reduce the effect of the largebody-movement of the second person on the sleep of the subject byadjusting an adjustable parameter, the control unit being configured togenerate the recommendation, and (B) the adjustable parameter isselected from the group consisting of: a parameter of a mattress onwhich the subject is sleeping, a parameter of the bed, a sleepingarrangement of the subject and the second person, and a room-environmentparameter, the control unit being configured to generate therecommendation to adjust the selected parameter.
 14. The apparatusaccording to claim 11, wherein: (A) the sleep-disturbance outputincludes instructions to a device to adjust an adjustable parameter, thecontrol unit being configured to generate the instructions, and (B) theadjustable parameter is selected from the group consisting of: aparameter of a mattress on which the subject is sleeping, a parameter ofthe bed, a sleeping arrangement of the subject and the second person,and a room-environment parameter, the control unit being configured togenerate the instructions to the device to adjust the selectedparameter.
 15. The apparatus according to claim 1, wherein the motionsensor consists of a single motion sensor.
 16. The apparatus accordingto claim 1, wherein the control unit is configured to identify that aportion of the motion signal was generated in response to motion of thesecond person, and not in response to motion of the subject, byidentifying that the portion exhibits ringing.
 17. The apparatusaccording to claim 16, wherein the control unit is configured toidentify that the portion of the motion signal generated in response tomotion of the second person exhibits ringing by ascertaining that theportion includes a set of at least three consecutive extrema each ofwhich is separated from the preceding extremum of the set by a time thatfalls within a given time range.
 18. The apparatus according to claim17, wherein the time range is 0.15-0.45 seconds.
 19. The apparatusaccording to claim 16, wherein the control unit is configured toidentify that the portion of the motion signal generated in response tomotion of the second person exhibits ringing by: ascertaining that theportion includes a set of at least three consecutive extrema each ofwhich is separated from the preceding extremum of the set by a time thatfalls within a given time range, and further ascertaining thatrespective differences between (i) magnitudes of the set of consecutiveextrema, and (ii) a magnitude of an extremum that precedes the set ofconsecutive extrema, fall within a given amplitude range.
 20. Theapparatus according to claim 19, wherein the given amplitude range is10%-150% of the magnitude the extremum that precedes the set ofconsecutive extrema.